You'll have some problem with KickAss Torrents - the original has ceased.
Two good sources for music are usenet and good ol' youtube. Some amazing hard to find music there and there are plenty of download helpers around.
Not positive about private music trackers - they do seem to be elitist, and I'm not talking about the music.
Haha. Well, shows how much I've bothered to try using KickAss since getting into other trackers! Youtube is definitley good for sampling a lot of different music, and there's literally shit tons of even very obscure recordings on there, though ripping audio from youtube is far from an ideal solution. I'm not knocking it, though. I've done it too as a last resort when all other sources failed to turn up results.
As for private music trackers being elitist, I am not sure what you mean. True, they have a lot of rules, but that's because they typically have high standards for torrents uploaded and for the users who download them. As with any tracker, you should seed for as long as possible. Pay it forward and you'll be rewarded with the privilege of being allowed to remain a member, which is really simple and not a lot to ask. High standards are a good thing, because they offer some guarantee that you'll get quality torrents and reliable seeders more often than not.
Or do you mean the users themselves are elitist? From my personal experience, a lot of people on private music trackers who are really active in their respective forums are your typical annoying, college-aged wannabe-bohemes, trendies, "hipsters", etc., but, fortunately, you don't have to interact with them just to use the trackers. At any rate, I wouldn't call them "elitist" per se. Annoying, yes, but not really elitist.
Just my two cents, of course. If the other suggestions suffice for the OP, that's fine too. I don't expect everyone to be as anal about lossless files and logs and CUE sheets and 24-bit vinyl rips I can't tell sound any different from 320Kbps rips (but can "feel" the difference :
) as I am.