While not an Iowan myself (unfortunately), I've spent many a summer fishing there (my relatives live there). Lake Chariton may be a bit out of your way, but I believe it's known for large bass and flathead (correct me if I'm wrong, but I believe the state record flathead was caught in Lake Chariton by the dam using a piece of shrimp). Lake Okibojee is a great spot for Muskie, pike (It might just be one or the other; I forgot which), bass, and I believe wipers are stocked (white perch/ striped perch hybrid).
River wise, Iowa has great fishing. The Raccoon has great channel cat, but it's also infested with carp (which, incidentally, make great cut bait). You'll also be right next to the Des Moines River, which goes through the heart of the capital. To the east there is the Cedar Rapids River (or is it just the Cedar River?) which has trophy catfish and pike, as well as the Whapsapinicon ("Whapsy"), which has plenty of pike, bass, walleye, and catfish. It also has drum, but I don't really fish for those much.
There are also plenty of farm ponds with stocked catfish and bullheads. Ask people where the best spots are- Iowans are friendly. They'll help you out. And if you're into catfishing, there are plenty of slaughterhouses to get bloodbait from. If you like more active fishing, go to Lake Okibojee.