Visit London/Britain:

Invaluable resources for visiting London are the Visit London and Visit Britain websites. The British may be a cold standoffish people, but their websites sure know how to welcome you.

Update: Since writing that snarky comment, I’ve returned to England and what a difference ten years makes. Everyone we met was as friendly as possible, many people going out of there way to offer assistance. Yes, in my experience tube travelers were still as quiet as the grave but another American related a story of being in the tube and quietly singing Happy Birthday to her friend when all the passengers in the car joined in singing. And you can get ice in your drinks, even unasked (I think if they recognize you as an American), but it’s still doled out three cubes at a time.