HHV.de has a fantastic selection of vinyl records, featuring many music styles such as hip hop, grooves, rock, reggae and electronics. Only a small part of the records is available in the real store so if you don’t find what you are looking, you might find it when you look thru their online catalog. You can easily look up a product and order (all by yourself) and then pick it up the next day, of course without any extra charge.
The store has also a great selection of clothing and other accessories. HHV.de is definitely one of Berlin’s biggest online shop and so it is well worth checking it out.