The Tfarchive.com forums are practically a UK forum.
i like the TFarchive website. i wasnt aware it was a forum - might look into that
Full Metal Hero has been very good thus far.
I'm having problems locating the Geeky stores tho.
Be aware that TFarchive forums can be very clique-y and somewhat less than friendly is all.
Good site, but wear your asbestos undies for the forums.
TFArchive was one site I would use a lot until 2009, which was when they stopped maintaining checklists (so much movie stuff musta been too much for them).
They still have a great mis-transformed page though.
K - I'm now up north, but start with Forbidden Planet, Orbit and Gosh, all of which are a short walk away from each other. They're all great shops - FP is well-stocked with modern Transformers (Prime, Bot Shots etc.) and Orbit has lots of vintage ones, including Japanese and Euro exclusives. (Gosh is really only good if you're looking for comics.) If you catch the tube to Leicester Square or Tottenham Court Road (or anywhere nearby) you should be able to find them all. Good luck!