This is a truly silly homepage, just 'cos I've been experimenting with the tools. The best thing I can think of is to put some links to rather more useful web sites that could be interesting.
Some choirs:
City of London Choir
Anton Bruckner Choir
Imperial College London: Choir & Chamber Choir
Lyra Davidica
Exmoor Singers
(of which I'm not a member)
Morgan Stanley is where I work