Maybe things have changed, but before we left the area the Leatherhead dump had a little shop from which I bought quite a number of decent CDs - though I may have been prepared to pay £1 or so for each one I wanted.
Now I can get CDs in the local charity shop for 4 for the £1 or better, or sometimes the assistants count rather badly so we get "how many have you got there ?" "about 10" "OK call it £2" - also double albums often get miscounted too.

However a fair bit of filtering has to be done to get anything good - seems to go in waves. Occasionally it looks as though someone has just brought in a fairly big decent collection, which then gets drip fed out to the shop and mixed in with [for me at any rate] a load of trash.