Are you familiar with this site?
It's a music database containing many many releases, where you can add and sell records, underground or not.
It was rather used by grindcore and noise fans, but now metal takes more importance.
Positive points: Contrary to ebay or else, CDr and tape formats are accepted. It's a quite famous site, and it's not focused on a music genre, so you might be surprised to sell something weird...
Negative points: Everything isn't in the database, and when adding a release it's strict about requested infos.
I added a bunch of items from my distro, I took time to create all the entries for records that didn't exist, missing demos were numerous, but now it's in the right way. I hope it will increase sales a bit, at least it will fed an underground database.
http://www.discogs.com/seller/gabalgabow
I hope every underground bands/ labels were entering their releases, to help selling their stuffs...
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