I never purchased any music and am not subscribed to iTunes Match. Everything in settings is set to "no" or "off". I have unwanted, unpurchased music and want to get it off my iPhone. However, I have two audiobooks, sync'd through iTunes from my computer, that I do not want to lose. I have to ask Seri to open them, because I have no Audiobook section and can't find them otherwise.
As John Ramos said, you should sync your iPhone with iTunes on your computer, at which point you should have the option to sync audiobooks but not music.