Used record stores in London and Guildford, UK?

I'm visiting the UK soon and, while I don't plan on spending time shopping for music, I wouldn't mind checking out a used vinyl store while I'm there just to see what they're like.

I'm staying in Guildford and London (almost across from Hyde Park). Are there any shops that specialize in 1960's/70's used vinyl in those areas? Looking for rock (Beatles, Stones, Who, Kinks... the usual suspects).

 

check this out for london....

http://www.discogs.com/groups/topic/86292