Pontiac, IL has 4 free museums, including one on the history of Route 66 and John Whitemire (?) who drew a lot of murals up and down Route 66 In a VW van then later his 1966 school bus Land Yacht.
When we arrived at Pontiac, I forget who directed us to the 4H R Park and gun club, but it was great. They have stalls and open barns (I guess that is what they are called) so you could bring a horse if you wanted to go ride. I'm sure they can tell you where it is safe. The campground is away from the highway and very quiet and the hosts are very friendly. Pontiac has fiberglass vehicles - cars and pick ups with a wrecker in front of the land yacht. They are decorated in the theme of Route 66.
After going to the museums in Auburn, IN, we drove to Fort Wayne, IN and stayed at the Johnny Appleseed RV Park that was under a lot of shady trees. The price was $15 to 20 a night. Fort Wayne has free wifi. This park in within a city park.
While in Elkhart, IN we stayed at the Elkhart RV Park, which was an old KOA but was very clean. They had full hook ups with cable, clean laundry and showers. We paid about $200 for a week, I think with GS discount. In town, it is fun to drive around and take pictures of the fiberglass "elk" that have been decorated. Sometimes it is an extension of the building they are in front of.
At the Illinois/Indiana border we stayed at the Kickapoo SP that was electric, water is shared and you go to a dump site to empty black and grey water. It was quiet, had swimming in the lake as well as fishing and a playground area for kids and trails for hiking and biking.