copied from another thread.
Now the next thing you are going to need are some flies. That is going to all dictate on what streams you plan on fishing. There will be caddis and midges in just about every stream you fish and most of your mayflies. I would start out with some pheasant tails in sizes 10-20 and that will cover ALOT of bugs (mayflies and stones) with just that fly. Some caddis larvae in green, cream and brown will be another fly that you should have in sizes 8-18. Always have some zebra midges in your box. A hares ear and a price nymph will also be some other great flies to have. Those are just some flies that will get you started for fishing underneath where the trout will be feeding 95% of the time. For dries some BWO in size 16-20 will be good some Elk hair caddis in sizes 12-18 and some adams in 12-18 well get you going for most of your mayflies. Now i know i have wrote a lot of information but dont be scared by it all, just learn how to nymph fish at the moment and in about a month or so when that bugs starts to hatch pick up a dry fly or two and give it a go.