When I start my label, which will focus mainly on underground/extreme metal, I won't be posting ANYWHERE that I'm looking to sign bands. I will scour through facebook, myspace, forums, like I already do looking for new ways to promote my own shit. It'll be way more personal for me to find bands that I actually like, and not because they "sound good" or because they have a marketable appeal. It'll be those rare mutant bands that are actually being creative and producing real art opposed to cookie cutter bullshit.
Then I'll bring them into MY studio and I'll produce their albums based on MY experience and what I think REAL METAL should be. Then I'll send it off for mastering and be able to produce something that I feel is worthy of all the time and effort that goes into it. Then I'll get my bands booked on the huge Death Metal festivals, rent a van(s) and drive to these events myself where I'll probably be a sponsor of some kind and have a booth open to sell merchandise that I acquired by trading though the metal underground.
See I'm in my scene, half the fun is partying with the bands and jumping into the mosh pit when you're half drunk and ready to fuck some shit up. What I'm saying is a small part of a REAL game plan that a band in MY scene might read and be like "I WISH THEY WOULD SIGN MY BAND". You need cash to do these things. Know your scene and don't limit yourself to conventional record label methods. And the last thing we need is another netlabel. There is already enough net labels with no real funding doing the exact same things you're offering.
