This list is not yet complete, but just a quick start here. Also, there's a western trend, since I live in Colorado

Hatch Guide for Lakes - Jim Schollmeyer
Hatch Guide for Western ... Jim Schollymeyer

"Western Mayfly Hatches" Rick Hafele and Dave Hughes
I really like how they organized this book. I might suggest a few diffent flies for some of the hatches, but we all have our preferences.

"A.K.'s Fly Box" A. K. Best.
Another nice book, better for dries than nymphs, but then A.K. really prefers dry fly fishing (don't we all).

"Caddis ...." Gary Lafontaine
The guy does excellent research. I feel myself very fortunate to hear him speak a few years ago.

Now this is just a general comment on any and all these types of books. The pictures could always be a bit better. For example I think a top and side view of flies is a great aid to the beginner.

The other problem I see is I don't believe the colors are dead on. Now this is a very difficult thing to get exactly right, and I'm not sure if one really can. Every since Fuji started turning out film that made people and pictures look "better" than reality. Kodak, tried to stay the course, but I'm not sure if they have.

In any case everyone has switched to digital cameras ...