Well, you can spend the time, money and effort and drive the 1.5 hours to Atti-tuckey (aka Attica, IN). Incidently, just happens to be where the Bad Lands ORV park is located.
Or.... You can use the USGS 7.5 minute maps that cover the Hoosier National forest and go find open forest roads. But thats if you're willing and able to get your rig unstuck by yourself, or with others. I'm guessing that you're a student at ISU there in Terrible Hole, if the school has a geology department they should have set of Indiana topo. The DeLorme Gazetter of Indiana is a good map sourse but doesn't have the small forest roads on it. Try over in the area West of Mitchel, IN, using one of the USGS maps. Mitchel is about an 1.5 hours east of TH. Lots of mud if that's what you like, but then again you're in the midwest.
Good luck!