Great minds think alike, I was just trying to put something together for the FAQ section, so a lot of this is the same as Frank's list.
You’ve gotten great advice about going to Kaufmanns and having them help you get set up. Take your fly reel along with you and they can help rig some things up for you too. (They can attach your leader if you need it, and they can show you how to tie up a dropper or indicator.) They’ll also be able to help pick out appropriate flies.
Here’s just a general list of stuff, you can defer to local experts for the waters you fish (always a good idea) for specifics, but just to give you a general idea, and it you want to go to the Kaufmanns site to browse around to get a look at some of the stuff and fly patterns:
Leader- A tapered knotless leader, generally as long as your rod, either 7 ½ to 9 feet long. For trout, a 9’ leader tapered to 4X would be a good start. You attach the heavy thick end of the leader to the fly line with a nail knot., or if your fly line has a loop in it, you can attach the leader with a loop to loop connection. (Leaders will run 5 somewhere around 5 bucks for a pack of 2). If you buy this in a fly shop, bring your reel along and have them rig up a loop on the end of your fly line to be able to attach leaders easily down the road. Here’s a thread with some embedded links for knots and attaching loop to loop connections:
Grog's Fishing Knots Index
Loop to loop connection:
Tippet- Get a couple of spools of tippet to add to the end of your leader. This will prevent you from chopping up your leader as you change flies. You would add about 2’ of tippet to the end of your leader. The “size” of a leader or tippet is measured by the diameter of the line. The bigger the “X” the thinner the tippet (or leader). The size of the tippet is determined by the size of the fly. Larger flies, thicker tippet, smaller flies thinner tippet. To get a ball park idea of what size tippet to use, divide the hook size of the fly by 3 to get the size tippet to use. So a size 12 fly, divided by 3 = 4X tippet. A size 16 fly would be a 5X tippet, an 18 would be 6X. A couple spools of tippet (4X, 5X and 6X) will cover you for a large range of flies used for trout. You attaché the tippet to the thin end of the leader with a double surgeon’s knot. The free end of the tippet then goes to the fly with an improved clinch knot. (Spools of tippet go for 3-4 bucks a spool)
Dry Fly Floatant – a paste type floatant like Gink will help prevent dry flies from getting waterlogged. (3 bucks)
Micro Split Shot- for pinching onto your leader or tippet for sinking nymphs. Because of concerns for the environment, and increasing regulations., non toxic (lead free) split shots is recommended. (2-3 bucks)
Indicator- there are many different options, but these are used with nymphs to serve as a “bobber” to signal when fish has eaten your nymph and to control the depth it fishes. Alternatively you can use a dry fly and tie a short section of tippet to the bend of the dry fly (with an improved clinch) and hang a nymph off that fishing 2 flies at once. (2 bucks)
Nippers- for trimming tag ends of knots and changing flies. Get one with a little needle thing for cleaning the eyes of flies (they sometimes get clogged with head cement that prevent you from threading tippet through. (2-3 bucks)
Hemostat – for taking hooks out of fish or your fishing partner
They’re also handy for pinching down barbs, and split shot. (5-6 bucks)
Zinger- this is a thingamagig that pins to your vest and has a retractable cord with a clip on the end. You’d attach the clip to your hemostats and nippers to keep them out of the way, but keep them within reach. (2-3 bucks)
Landing Net or Ketchum Release tool- up to you if you carry one, but if you do you might want to consider a net with rubberized mesh (easier on the fish).
French clip- this is another gizmo that attaches to the back of your vest, It has a pinch type release that you squeeze to release. You’d hang the net from that so it’s out of the way, but can get to it if I mean when you need it. (3 bucks)
Waders These may not necessary depending on where you fish, many people “wet wade” in shallow streams or warm water environments. But for many, waders will be necessary. There are many options including rubber, neoprene and breathable, A breathable pair of will offer the most comfort in warm weather and, with appropriate layering of synthetics like fleece, be toasty warm in cold weather. Waders are sold as “boot foot” or “stocking foot”. Stocking foot waders are worn with a pair of wading shoes and offer the most support for ankles or cobble bottoms and will be the most comfortable to walk in. Prices can vary fro 80 dollars or so up to 700. I’d recommend buying a pair for 100-150 or so from a company that offers a lifetime guarantee. I’d recommend chest waders, they’ll cover you for deep water and splashes, and many can be rolled down to waist height for warmer weather and shallower wading.. They are available in women’s sizes
Wading belt and suspenders. Many waders will come with them, but make sure. The belt is good for keeping water out if you take a spill or step in a hole. You can fold chest waders over the belt too in hot weather to turn them into waist high.
Wading staff- probably not necessary right off the bat, but if you wade fast water streams or have a lot of uneven rocky stream beds having a collapsible staff (Folstaff or Simms) can be very handy. You can unfold it when you need it for crossing streams etc, and put it away when you don’t. Even though you may not need it right away, it’s good for you to know that they’re available if you have trouble with footing.
Polarized sunglasses- cut the glare from the surface and give you a better chance of seeing fish and the bottom. They also offer some degree of eye protection from hooks whizzing around. Brown, copper, amber type colors tend to be the best colors for contrast.
Flies- a local shop can help you pick out some favorites for the waters you fish, but in general you’d want a selection that covers a lot of different bases—to cover the water column, to fish in different current speeds and to imitate a variety of different critters. So some dry flies, wet flies nymphs and streamers would be a good bet for trout.
Vest- something with a few small pockets up high on the front for dry fly floatant, split shot, a pack of leaders and tippet spools, and a can of your favorite chewing tobacco. some zippered compartments for fly boxes with easy over sized zipper tabs, and a large pocket on the back for raingear. Prices vary from 20ish on up.
Camera- either water proof or in a heavy duty zip lock bag for your illustrated trip reports and hero shots.
Fly boxes- one with “micro slits” or compartments for dry flies so the hackle doesn’t get mushed. For now you could probably use this for everything, but as you add more flies, you’ll also want to add a few different types for different flies. You can get an unbreakable plastic 10 compartment fly box with brass hinges for now for about 6 bucks. Make sure it fits in your vest, and has compartments that are deep enough to prevent all your flies from blowing out.
Lucky fishing hat- the brim will also help cut glare, and it’ll protect the back of your head from hooks. A ball cap is fine, but make sure it’s a lucky one.
Flies- a local shop can help you pick out some favorites for the waters you fish, but in general you’d want a selection that covers a lot of different bases—to cover the water column, to fish in different current speeds and to imitate a variety of different critters. So some dry flies, wet flies, nymphs and streamers would be a good bet for starters and will give you a good collection to build on. Again a local shop will have better suggestions on specific patterns and sizes for the waters you fish, but something like this would be in the ball park:
Parachute Adams (size 14, 16) Imitates medium and dark bodied mayflies. Very effective widely used pattern. Good for slow to moderate sections of water.
Parachute Blue Wing Olive or Blue Winged Olive Sparkle Dun (size 16, 18) This imitates several species of mayflies that occur everywhere throughout the country,including Oregon, and are one of the first hatches in the season to start, and will continue through spring early summer and again in the fall. Good for slow to moderate sections of water.
Elk Hair Caddis sizes 14 and 16. A must have pattern, imitates a variety of caddis, and is good for fast, slow and medium fast water. Tan body light wing, olive body brown wing will cover a lot of bases.
Royal Trude or Humpy- size 14 These are heavily hackled dry flies that float well and are easy to see in fast water. Either one would be good to start.
Eventually you’ll want to add other dries as the weather warms up and more hatches kick in Yellow Stimulators, light bodied dry flies, Madame X and grasshoppers etc, but by then you’ll know what to get.)
Bead Head Pheasant Tail Nymph 16, 18 imitates a variety of thin bodied mayfly nymphs. Nymphing can be difficult to learn at first, but you can use these with a dry fly as an indicator near the surface, or behind a heavily weighted fly like a woolly bugger, hanging it on a short 12” section of tippet from the bend of the hook with an improved clinch knot .
Bead Head Gold Ribbed Hares Ear- size 14 Another very effective pattern for larger fatter bodied nymphs.
Other nymphs to add down the road, Bead Head Prince, Stonefly nymphs, Copper John, Zebra Midge etc. as well as some other sizes of above, but those would be good basics to start)
Partridge and Green and/or Partridge and Orange- size 14. These are impressiontistic flies that imitate drowned adults, emerging mayflies and caddis, and are very good searching patterns that are difficult to fish wrong. A good way to fish them is to cast at an angle down and across stream, and let the fly swing below you.
Deep Sparkle Pupae- Green body brown head size 14. This imitates an emerging caddis pupae and can be fished the same way as the soft hackles but will get a little deeper.
( there are other patterns for specific hatches that you’ll want to add—a Orange body brown head size 6 for the October Caddis hatch in the fall, but that’s down the road)
Bead Head Black and/or Olive Woolly Bugger size 8 Another fly that’s hard to fish wrong, imitates a lot of different things from stonefly nymphs, large mayfly nymphs, leeches and minnows in sort of vague way, but works very well. It is also very effective used in tandem with another smaller nymph hung off the back. This can be very effective in pools, lakes and in fast currents.
Muddler Minnow- size 8 or 10 a very versatile pattern. Imitates sculpins found in most western streams, and can be even fished on top as a grasshopper pattern. This is a very good pattern to use if your casting is a bit off. You can just drop it back down stream by feeding out slack fly line in current and steer it into lies – in front of rocks, into current seams, or along the bank.
Black Marabou Muddler Minnow size 6 This can be weighted with a conehead (heavy and awkward to cast, but gets deepest), or with wraps of lead wire (easier to cast). This can be a very effective big fish fly and is very good in high or of colored water. It can be cast and retrieved through pools, along banks, and can be very effective in ponds and lakes.
(other streamers to add down the road would be Muddler Minnows in size 8 or 10, Dark Spruce 8 and other classic Western patterns. )
Hope this helps a bit.