My Wife and I camp last year at the Rafter J Bar Ranch ( Camp Ground) in Hill City SD. I would highly recommend this camp ground. We had a pull through site with full hook-ups including cable tv, approximate cost was $44 a night. This camp ground has several different camping areas with different features and prices so call ahead.
This is a very good area for site seeing, we went to Crazy Horse, Mt Rushmore, Deadwood and Silver Lake ( I believe). Spent 10 days there and enjoyed everyone of them.