They offer free camping in Evarts KY which is a few miles up the road from Harlan and right next to the park. You can camp and ride your 4 wheeler or whatever it is you ride from town to the park. There is also tons of places to rent for a few days in town. The Ridge Runners are a great bunch of people and if you ask one of them will guide you just about anywhere you want to go in eastern KY.

http://rr.kyoutdoors.com/

I always have a great time down there, hopefully you will too!