In addition to the wonderful spring creeks in WI's Driftless region, to your east you have the storied waters of MI. We have another fly fishing site with an informative forum that you will want to look at:
www.UpperMidwestFlyFishing.com
A couple of books that should find their way into your fly fishing library are:
Fly Fishing Midwestern Spring Creeks and
Flies that catch trout (UpperMidwest year-round guid) by ross Mueller.
Ironically, we are going to fishing in your home waters in East Tennessee for the first time the first of week of May. I am looking forward to the trip.
Best,
David Dornblaser