Facebook ads seem to be the best way to go, according to the music marketers that I’ve followed. I purchased an online Music Marketing course and pay a monthly fee for access to an online forum that deals with marketing and promoting independent music. The course is called Music Marketing Manifesto (MMM) and the forum is called The Insider’s Circle. John Ozjaca is the guy who runs the whole operation (I might have spelled his last name wrong).
Youtube seems to be a place with great possibilities as a far as promoting your music too.
Check out this youtube video. This guy isn’t a believer in facebook ads but he has some useful info. https://www.youtube.com/watch?v=me4Wwtneh6s