Keyhaven, Hampshire - shingle beach with rocks in places. Also try Hengistbury Head as there's more of a beach there than Kimmeridge Bay (although the light is exceptional at Kimmeridge with an outgoing tide exposing the ledges).
Have a scout round Adam Burton's site for inspiration: http://www.adam-burton.co.uk/gallery/index.php?cat=50
Mupe bay and stair hole are also good, either side of lulworth cove.
Feel free to check my site, probably not quite up there with adam burton, but it has a fair few places around dorset in it, that might help.