Last year I read Hemingway on Fishing and enjoyed it, even though I'd already read most of the excerpts in their originally-published form. A nice collection of some of Ernest Hemingway's fishing-related writing, including what must be my favourite short story of all time - Big Two-Hearted River.
Another enjoyable read, with a New Zealand flavour, is Derek Grzelewski's The Trout Diaries. Kennedy Warne (founding editor of New Zealand Geographic, amongst other things), states on the back of the book that it will "satisfy angler, adventurer and philosopher alike." - I couldn't agree more!
I also recommend Mark Kurlansky's Cod - A Biography of the Fish That Changed the World - it's a great book. I'd like to write something like that one day...