What.cd is hands down the best site for music.
You can get in through the interview system they have. Unless you already know a lot about encoding files, such as what these all are ,V0, V2, 320kbps, Ogg and Flac. You'll have to know what a transcode is, and beyond that if it's a good transcode. You'll need to know how to look at the spectrals of the file and be able to tell if it's a transcode from a non-lossless format. There will be some other questions also, but those are mostly general knowledge.
That might sound like a lot of work, but it really is not for what you will get out of it.
This site will tell you everything to need to know to take the test and pass.