For you (especially southern) Minnesotans, I'm giving a couple more resources/recommendations. I would love to hear what others have been up to, so's we can all learn from one another.
Root River: I spent a couple great days on the Root this summer from near Chatfield to Rushford. I followed the route info given in Paddling Southern Minnesota (A Trail Books Guide) by Lynne and Robert Diebel. Travel much faster than I'm used to on flat water, which was fun. Public camping available at DNR sites. The book itself is a great resource, saving lots of planning time for novices. Most valuable are the sketched maps with stops and mileage and the recommended water depths for different waterways.
Whitewater State Park: I've camped here twice, once more casually and once just last weekend with a more hiking-oriented friend. We covered most trails in the park in a half-day, so again not much for hiking distance, but the quality of rare, ridge-top southern MN hiking was very good. The camp is down in the valley, most trails are up in and atop the sheer bluffs and are surprisingly scenic. Best bluffs I've seen in southern MN outside of the Mississippi, and the scenery is a bit more in-your-face than most even on the Big Muddy. The Whitewater is a trout stream.
Forestville/Mystery Cave State Park: Another small park. This is one I've only visited briefly, but I'm writing in anticipation of warmer weather when they run a many-hour "wild cave tour"/spelunking for qualified groups. Fortunately I know an employee there who will be leading these crews next summer. Something unusual for our area if you're looking for variety. The "tourist" cave is also very special for being in this part of the country.