A great place to start is with John Ross' TU's Guide to America's 100 Best Trout Streams.
Id go with justfishing on that one. There are a whole lotta places to cast a fly in America, and alot arent mentioned in the book. (But my local mountain stream is!! Come on up here!) Anyways, if youre not limited to the continental US, Id consider looking at Alaska. Ive always wanted to fish in Alaska. I will also vouch for everyone else's suggestions: Yellowstone, Bozeman, and you could always head to the Catskills and fish those classic dries
. Ahhh........ So many tout, so little flies
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