I hear Shelby Forrest is a good place to camp, but I don't know about for an extended time or what type of services they have. Its kinda out a little bit, but if you're here during hunting season there is restricted hunting allowed there.
Shelby Farms is pretty centrally located within the county. I know it has full hookups.
There's a KOA at the Lakeland exit, but I dont know much about it.
I guess it depends on why you'll be here and where you'll be spending most of your time.