I don't know if this is the right place, or if there is a right place, but I wanted to mention two things: the Septic's Companion, which is a great American-British dictionary (and fairly funny to boot), and the Septic's Companion forum, which currently has less than a half-dozen active members.
You can find them both at septicscompanion.com. I thought it was great - I found the site before I went to England for the first time (well, only time, so far, but I plan to go again).
(didn't mean to ruffle any feathers if this isn't supposed to be here!)
