Hi, I did a database for hillforts last year its on the yahoo group, Somerset, part Gloucester also, and then started Wiltshire but got bored with it and lost the map I was taking it from. But have done the local ones round bath, as probably Jamie has, I probably blogged those.
The thing about hillforts is not much excavation or information around.
The ones round Bath are; Littledown, Stantonbury, Solsbury and Bathampton. Just down the road on the Cotswold are Horton, Old Sodbury and the Hinton/Dyrham Fort.... the following link should take you somewhere ;)

http://groups.yahoo.com/group/hill_forts/files/DATABASE%20-%20Group%20members%27%20data/