There is a "member map". You can scroll and zoom to near where you live. If people list a recognizable address in various forms, their member name will usually pop up.
There are a few people that only show up as balloons, not names. I don't know why.
http://garden.org/users/member...
But I only see Dragonlady and you listed in Wales. After that, it's Coventry or Manchester. (But there might be more people who listed their address in a hard-to-recognize form)
There is a British regional forum with "UK" in its URL:
http://garden.org/forums/view/...