Andy's long-time boyfriend, John Giorno, did a few records with the likes of William S. Burroughs, Philip Glass, Laurie Anderson (her earliest stuff), The Fugs, artist Claes Oldenburg, poet Frank O'Hara, and Patti Smith.
They are up for legal download at ubu.
http://www.ubu.com/sound/guy.html
http://www.ubu.com/sound/big_ego.html
those are the best two, but a complete list of downloadable Giorno recordings is here:
http://www.ubu.com/sound/giorno.html