Two men knew that situation and created this website: www.thelabelfinder.com, where you can search labels shops in certain cities in German, English or Spain. About 7000 labels and 10000 shops are represented - most of them in berlin, hamburg and munich, but also for tokio, barcelona and new york.
So if you are searching anything have a look at the site. It's worth a visit.
(picture: screenshot of thelabelfinder.com)