I have Lidarr setup to track album and singles releases from a handful of artists and bands that I am really, really into so I don't miss something. Mostly, though, I acquire new music the same way I always have, something catches my ear somewhere and I go looking for it.
Discovery is kinda all over the place, but lately Youtube has been pretty good at suggesting new artists and tracks to listen to, though, it is occasionally hard to actually acquire said track or album. Other places have movie and tv show soundtracks, ListenBrainz recommendations and occasionally an actual radio station..
For the most part, I've moved away from pirating music and audiobooks as it's generally pretty easy to find an above-board source that is either DRM free or can be cracked easily. When I do pirate something for whatever reason, I'll usually go back later and purchase a copy. I would rather support the artists since I usually have the means at present and most of the artists I'm into aren't really all that big. I really wish that ebooks, tv shows and movies would get the damned hint and do the same..