okay, this is a long shot, but bear with me.

I'm looking for a sci-fi novel, a pretty old one, probably 80s or earlier, set in a dystopian future with lots of virtual reality based drug use (i think?) and nutrition nuggets and the plot was something about rock stars? people pretending to be rock stars? there was a keyboard on the cover. one of the characters was like an over-sexed latino glam rocker, one was a fat girl who was pretending to be a diva...god, i don't even know. i can't remember the name or the author to save my life. does this sound at all familiar to anyone?