White River RV Park & Campground in Montague (just north of Muskegon) is nice. Decent sized sites, most fairly well shaded. Close to Lake Michigan and canoeing.
As pc35 mentioned, the Wayne County Fairgrounds is close to Greenfield Village and the Henry Ford Museum. It's just a field with full hookups but is reasonably priced.
If you don't mind staying at an electric only site (fresh water and dump station onsite), I'd recommend Michigan State Parks:
https://midnrreservations.com/
https://www2.dnr.state.mi.us/parksan...t.aspx#map-tab
In the UP, I recommend Tahquamenon Falls State Park, Muskallonge Lake State Park, and Porcupine Mountains Wilderness State Park - Union Bay Campground.
In the LP, most of the State Parks along Lake Michigan and Lake Huron are nice.