We stayed at Smoky Bear Campground last September, and really enjoyed it. It's a little out of town but not too bad a drive, on Hwy 321 east of Gatlinburg. Not too big, nice facilities (clean shower house, nice playground, small pool.) You can also go to
www.rvparkreviews.com and get some good reviews of parks in that area. Mcgyvers wife (Mrs. Mcgyver?) has written some excellent reviews on that site.