burlmart,
Try the National Parks and National Forests. Take a look at the Evangelene National Forest on the lake up by Alexandria and I think you will find a couple of examples of NF campsites. Some National Wildlife Refugees have campsites, most with no hookups. When you get into the National Forests in places like Arkansas, Missouri, Tenn, Colorado, NM and so on, you will find lots of "boondocking" campsites. You might take a look at the "campgrounds" posting forum on RV.net. Also, Corp of Engineers have lots of campgrounds around their lakes.
We only stay in a KOA style campground getting to these kinds of places. Try it and you will like it.
If you are a AAA member, they can provide you with camping booklets listing all campgrounds, commercial and public for the US and Canada.
PSW