We rented a static mobile home in Nagle's campsite in Doolin last year. There were plenty of tents on the site. Don't know prices. Extremely clean and tidy site. There were the odd tents and vans on the grassy cliff top (just S of the actual crag) most of the time we were there, which is obviously free but maybe a bit risky given the amount of sightseer trafic along that stretch of road.