To find record stores is not at all difficult in London. I simply went to SOHO and walked a bit off the beaten path. Go to the Oxford Circus Underground station and start walking in a direction that looks like it doesn't go anywhere, and you'll find a record store. There are many tiny stores that specialize in selling vinyl records. Most of them sell various kinds of electronic music or hip-hop. They are a blast. Most will let you listen to anything you want on turntables with headphones. The records are generally fairly well-priced, too, at around 10 to 15 pounds. The only problem with this is bringing vinyl back with you if you are on vacation; if you have a small suitcase, you might want to go for CDs.