London Record shops / shows

Hi! I'm gonig to London and I was wondering if someone could advise me were I can find some record stores that have experimental, jazz, alternative music (that sell 2nd hand cds or cheap cds) If possible near a metro station, once I dont know London at all! Thanks! also, are there any good shows untill the end of August? _________________________________________________________________ MSN Hotmail, o maior webmail do Brasil. http://www.hotmail.com