I was reffered here by a Jeep site. Looks like I may not be the only one...
I just got a Jeep and into offroading this fall. So I have only been one place. It is in N/E IL though. The Cliffs Insane Terrain: Cliffs Insane Terrain
Worth the drive IMHO. Pretty fun. We went winter wheeling during the blizzard in Dec.
I have hooked up with a local club. Most of their events are in the warmer months, but it looks like it is mostly private property.
I have been searching for legal places also.