Benford: Yes WY has a wonderful selection of trout to go after. Here is a starter list: Nymphs: scuds, brassie, bloodworm, copper john, disco midge, crystal midge, rojo midge, dragonfly nymph, pheasant tail and bead head PT, flashback PT, hare's ear, marabou damsel, march brown, 20 incher, prince nymph, rainbow warrior, san juan worm. Dries: adams, BWO. chernobyl ant, hoppers, elk hair caddis, x-caddis, zwing caddis, fat albert, ants/beetles. An sortment of streamers: wooly bugger, leech, egg sucking leech, hot head leech, bite me buggers, muddler, zonker, zoo couger.
Leaders I use are 7 1/2 ft to 9 ft for streams and 12-15 ft for lakes. I primarily use 3x to 6x for leaders and 3x to 7x for tippet.
Here is a link to the fly patterns listed on Charlies Fly Box (a fly shop in Denver) virtually anything there will work in WY. Click on the dropdown box near the top just under Charlies Fly box.
Charlie's FlyBox - Colorado's Best FlyShop and online Fly Tying Tutorials