In reply to Tim.W.Climber:
As others have said:
Rockfax - West Country Climbs - select routes with good photo topos
Nick White - South Devon and Dartmoor - definitive guide b&w topos, out of print
Rockfax - Deep Water - covers the DWS routes
Javu.co.uk - again covers DWS
Whatever you do make sure you check out the bird restrictions first which affect all the great cave routes and chunks of the DWS stuff.