We stayed at Leisure Lake RV resort-
Home two weeks ago. It is just as nice and neat as the pictures depict. This is a membership resort-however, membership in PPA, GS, or Escapees get you in. We paid $35/night with GS membership card. I suspect during the races prices may be higher. Mike, the manager, is nice and helpful.
Getting there is a hassle through the road construction, but doable. Hopefully ILDOT will have the new interchange finished on I55 to Frontage Road, just 1 mile North of I80, which will make very easy access to the resort. They do not make reservations, which may be an issue for the races.