In reply to Enty:
I went about 8 years ago. From what I remember there were two campsites, one which was walking distance to the rocks, but seemed smaller and not quite as nice, and another which was bigger, a bit nicer, and about a 10minute drive to the rocks. I'm afraid I can't remember the name of either.
Most people stayed in their vans in the car parks in the national park (it had something of a party atmosphere), although if you choose this option there aren't any toilet facilities within the national park.
It was a lot of fun and I'd love to go back. We did a mix of bouldering and sport which was ideal as the sport climbing on the slabs gives the skin on your fingers a bit of a rest. The granite is very sharp.