The Longest Silence by Tom McGuane.
The River Why and River Teeth by John David Duncan (even though he rips fly fishing guides in both)
The Moon Pulled Up an Acre of Bass by Peter Kaminsky. (especially if you liked "Guide House" on ESPN). Fly Fisherman's Guide to the Meaning of Life : What a Lifetime on the Water Has Taught Me About Love, Work, Food, Sex, and Getting Up Early is good too.
The Snowfly by James Heywood. The only novel to ever credibly blend fly fishing, cold war espionage and political intrigue.
All of the books by E. Donnal Thomas Jr. are tops. (Hunting with longbows and fly fishing in Africa, Alaska, Siberia and other remote places). Be sure to put the "Jr." part in if you do a Google or other search. His father won the Noble Prize for medicine (his dad is from Mart, TX and a teasip) so you will get a lot of information on cell transplants and cancer research if you don't. Jr. is a doctor in Montana.
p.s. Gierach’s books are great, but if you love Gierach the author, don’t ever meet Gierach the person.
[This message has been edited by 87Flyfisher (edited 6/27/2008 9:01a).]