Ah, Politics. The lifeblood of any city. I guess as good a place to start is the London government website http://www.london.gov.uk/.
London held elections for a mayor in 2008, and we elected Boris Johnson.
The website http://www.londononline.gov.uk/ gives an easy way of checking who your parliamentary & council representatives are. This seems to be part of 'LondonConnects' which talks about 'e-Government', whatever that is.