I'm a big fan of live music, and am lucky enough to be house photographer at a number of venues across London. Here's a mix of links to some cool sites and venues that I shoot at, plus some others that are great at promoting new bands.
Rockshot, a great live music site: rockshot.co.uk
Licklist: clubs and bars across the UK Licklist
Musical Pictures : my best mates site musical pictures.co.uk
KOKO, Camden Town. A beautiful venue and a great place to see new breaking bands: www.koko.uk.com
The Garage, Highbury and Islington. 2 venues in one building! thegaragehighbury.com
The Barfly, Camden : Hidden above a pub the Barfly is one of London's greatest small music venues. thebarflylondon.com/
The Jazz Cafe: World famous as a venue but don't be fooled...its not all jazz! thejazzcafelondon.com/