If you're staying in Cheddar be sure to see the caves there. Also
get a ride down to Wells, The cathedral there is amazing and the
Evensong performances are not to be missed even if you're not the
Evensong -- Performances??????
You'll have all the old bishops spinning in their graves and risk
being stuck by lightning on the way home if you go to any service in
the Cathedral expecting to be entertained.
But to go back to the original question; this page may help
http://www.craftscouncil.org.uk/Nationalguide/SWA.html but in
general you will need your own transport if you are going to get to
any of the local towns.