We at Glosfolk maintain a (free) folk directory - for performers, and a (free) diary of events in and around Gloucestershire. As some of the contributors to this thread have mentioned it is of course very very time consuming. We do not let people update entries themselves, so keep a handle on what is included (To make sure it is actually 'folk' and not rock 'n roll, etc)
It is at Glosfolk

Directory categories on left, Diary at top of page