Brian Hendershot said:
Just remember that London is really bloody expensive. It might be better to stay out of that area if possible. A good thing to remember is that the further North you go, the cheaper things get. (well, they also get more anti-Tory [our current ruling government party] as you go further up North, but thats a good thing really
Also, try not to get into a political debate with us. Trust me, the political ideaologies are a bit... different... over here in Europe compared to America, and we can get a bit 'heated' when it comes to debates, particularly with the (many) people who aren't exactly happy with our current government
Lastly, bare in mind that you may encounter the odd protest march in London - look around the web, find out when/where such protests are happening, and try to avoid them if possible. Depending on the type of protest (student protests are particularly volatile), police will use a tactic known as 'kettling', where they surround the protesters (and any unfortunate passers-by along with them) and trap them in a confined space -this is very well known to cause a rather large amount of violence, so avoid such situations as much as possible.
Other than that, Britain in general is a very multicultural nation, and London is particularly so! Your probably not the only one who's unused to London, so I'm sure they'll be plenty of things designed to help people such as yourself