In reply to Paul Sagar:
Yep, echo the Rockfax guide and that campsite (though it can be windy!) And when you stay at that campsite, the Wyke Smugglers is a decent pub nearby. Though if you want to eat in a pub on the island the Cove House is the one to go for, excellent food and a decent range of drinks, though it can be busy so you may want to book.
The campsite is called Martleaves Farm, it also has a B&B attached.
One thing of note - some of the approaches can be awkward, and so if you're "cack-footed" like me (is there such a thing? ) a hiking pole can be useful to avoid falling 50 feet into the sea.
Another thing of note is that travel by public transport is unusually feasible for a climbing area. There are 4 buses per hour (number 1) onto the island from Weymouth (Kings Statue) at most times of day, including Sundays, and none of the climbing areas are a particularly long walk from it.
Finally, and I was looking for a thread to put it in, if you do find yourself there without a guidebook there is a small old-fashioned independent bookshop in Weymouth called Books Afloat that stocks it, this appears to be the only place in Portland/Weymouth that does, though give him a few days to get another one in as I bought it on Saturday!
All in all a great place to do some sport climbing (and routes for all abilities, too), on a hot summer's day you can easily forget you're not on Sicily or somewhere like that.
Post edited at 16:16