OK, not looking for one, but I thought I'd be a bit cheeky and mention the one I go to, which has just got its own website up and running. I've been going there on and off for about 5 years, and the children have always really enjoyed it. It's not just Mums, there are a few Dads who go and it's also used by the local Childminders.
Anyway, you can find out more about them here
Spring Lane Baby and Toddler Group