One interesting way of discovering artists is finding an artist that I already like on a compilation CD, and then seeing what else is on the CD.

Music licensing (in the US at least) is actually pretty nice for this (from the licensee perspective anyway). There are mechanical licenses which allow you to use music for many uses without contracting with the rightsholders and clearinghouses whose job is to determine where to send royalties. So you can use the music and send reporting and royalties to the clearing houses and you're done.

Of course, you may want to contract with the rightsholders if you don't like the terms of the mechanical license; maybe it costs too much, etc. If you're Spotify or similar and you have specific contracts for most of the music, and have to pay mechanical license rates for the tail, it might make sense to do so in order to boast of a larger catalog.

So there was a clever trick that smaller artists did on what.cd: put up a really generous upload credit bounty for your own music, in order to sell digital copies.

I knew a few bands in Toronto who did this as a way to make sales.

They'd put up a big bounty right after setting up a webpage offering the album for sale via Paypal, then spend a few days collecting orders (and they would get a lot of them - hundreds sometimes - because What.cd had a lot of users looking for ratio credits) and then eventually email a link to the album after a few days.

No idea what the scale of this trick/scam (call it whatever) was but anecdotally I heard about it enough.

They also had good incentive structures for keeping the bar high -- you could get kicked out for having a bad ratio, so the easiest way to pump your upload up was to fulfil obscure requests for FLACs you could purchase online but were extremely difficult to purchase (if you're lucky it's just an unknown artist on Bandcamp). I discovered a lot of obscure music this way, some that I'm still looking for to this day after it shut down.

Because I cared so much about being part of that private tracker, this is what also prompted me to rent a seedbox for the first time. I paid in Bitcoin out of paranoia (I lived in Germany where the fines for piracy are HEFTY, and they actually do come after you) back when Bitcoin wasn't really worth that much, and later found that that old wallet suddenly had a couple thousand in it instead of the spare change I couldn't move!