Richmond Adult Community College do some comedy courses if anyone's interested and lives near enough:
http://www.racc.ac.uk/search-results.php?title=comedy
I've been the last two years and they are sketch-oriented. On one, it's nice to see your work performed by the drama groups at the end of the term, just to get an actor's perspective on it. The second course is new ("Collabrative Comedy") and is for writers/performers as you'll do your own stuff apparently.
Dan