Where can I find a database of music for genre analysis?

I've been working on a project to classify music automatically, working with the GTZAN collection, by George Tzanetakis. Its kinda small though, only 1000 tracks of 10 genres. Are there any bigger databases available for this kinda thing? For reference, the GTZAN collection is a set of uncompressed audio files, each about 30 seconds long. Something like this would be preferred. I've looked up the million songs database, but that only gives a selected set of data of each song, and doesn't give out the audio itself for analysis. I've also checked out the EchoNest API, but couldn't use it for the same reasons.