Sounds like you have your hands full already. Yes to Jason's referral to Ernie...My favorite short story being his, "Portrait of the Pere Marquette".
Yes to John Voelker (Robert Traver)...another Michigan treasure he was.
Nick Lyons writes some fine tales as well.
Yes to Louis' suggestion...His collection, "Fisherman's Bounty", if you can find it, is a collection of others short stories that you will re-read.
I'm partial to Charlie Fox..."This Wonderful World of Trout", and his "Rising Trout".
I'm reluctant to reveal this one, but, Datus Proper's, "What the Trout Said: About the Design of Trout Flies and Other Mysteries"...We lost him way too early!
Finally. Charles Ritz, "A Fly Fisher's Life: The Art and Mechanics of Fly Fishing".
Spence