On the left coast, a sinking line is essential. Most people typically use 200-300 grain Streamer Express - type lines for the surf.
A floating line is nearly impossible to stay in touch with unless the water is very calm, which is rare on most beaches here. With a floating line, you would miss many fish out here.
My go-to set up is a 9' 8wt. rod with a 300-grain Streamer Express line. I use about 4-6' of strait 8 or 10 lb. leader to the fly.
I would use an intermediate line for baitfish patterns, but a heavier line for sand crab or small crustacean patterns.
A stripping basket is also essential for managing your line. Otherwise, it is easy to get yourself tangled in your line with the surf action.
The trick to locating fish is to look for eddies, rip currents and "nervous water." As Rip Tide stated, the moving currents are similar to a river. Look for the seams and rips for the best action.
There are obviously different approaches to this, depending on location, surf conditions, and target species. I'm simply offering what works best out here.
Small clousers in neutral colors are fantastic producers.
Good luck out there.