There is a great trance data base called Psychedelic Mind Expander www.psydb.net, but like u said about discogs, there are no mp3s, but an idea u might want to use is quotes, I think this an excellent way for new listeners to find artists, especially if u have no idea who the artist is or what album a track is off, this is just how I got into trance, from an old mix tape I aquired, it was mostly Hux Flux, so using a quote from Experimenting from potions I searched google, now I've got Trance coming out of my ears, or going in rather.