I mainly listen to Japanese doujin music. It’s naturally good for discovery because many artists group together to form circles (independent labels) and release compilation albuns. I listen to the various annual compilation series I like, and every now and then there will be a new artist featuring on them so I’ll look up that artist and discover circles they feature on regularly. And when I discover a new circle, I naturally discover new compilation series and new artists.
The primary piracy resource for doujin music is Doujinstyle. One of the unique things about the doujin scene is that the pirates and the artists generally have a fairly good relationship. Most circles let Doujinstyle share their music because they understand it benefits them, and the minority who don’t submit requests to Doujinstyle who will always comply out of respect. As an alternative, these circles allow their music to be shared in the Doujinstyle Discord channels. Some of the artists even hang out in the Discord with the pirates. It’s a really interesting community that has formed over decades but never lost its tightknit feel.