Mix a things really. Radio shaped a lot of what I had growing up, a friend I adore had a wall of CDs as tall as me, she just buys whatever has a cover that looks even a little interesting. And for a wildcard, conventions. I picked up a pair of really sick experimental CDs at Anthrocon this past year specifically for her. That crowd had more than just CDs though - one guy was selling vinyls and cassettes even. Not that you’d know because that particular guy was in the age gated section since that was, shall we say not the primary merchandise he offered.
Another friend is into making experimental music and I like sticking the tracks they make into my playlists sometimes. Unreleased tracks go brr. And if I’m truly dry on tracks, I’ve got friends I think at this point in every timezone by now and pestering for some word of mouth recommends will always get me something new, language not mattering to me in the least ouo