Hey Rich.
There isn't many places to ride around where I live. Theres a few tracks here and there but thats pretty much it. I live in Illinois as well, up by Chicago area. Crystal Lake to be exact. Theres a track and trails in Rockford called Rocky Glen OHV park. It isn't much but its good enough for me.
And for a bike to start on I couldn't really tell you. I'm only 15 but i started riding when i was 10 on a 1976 Yamaha yz80. It mostly depends on what kind of riding you want to get into. I know a lot of people that just ride on trials and dont really do much track riding. I started out like that but soon Im getting a new racing bike. If your looking for a trail bike, I would definitely go with a four stroke. I have rode a Yamaha yz125, which is a two stroke, and that front end was hard to keep on the ground when picking up speed.
So it mostly depends on the kind of riding you plan to do.
I hope I helped you out a little bit.
Brandon.