Any good DVD or book will have some info on fly selection. It really depends on what you're fishing for and where. One good all-round pattern is a woolly bugger. (It's basically a chenille-and-marabou crappie jig without the jig head.) It will catch anything. I like white or chartreuse for crappie and black for bass and bluegill. Olive is very good for trout. Any standard trout nymph like a pheasant tail, hare's ear, or prince will catch trout and bluegill. Add some small poppers or spiders for topwater action.