if you are interested in hearing folk who can do really virtuosic things with their voice, i would suggest checking into the lovely strange world of sound poetry. a cool place to start is
www.ubu.com
try:
jaap blonk
henri chopin
bob cobbing
jackson maclow
kurt schwitters
hugo ball
john cage (the spoken stuff is very cool)
and cast about from there. there is a TON of material on this site.
while you're there, you can also check out my band
(which is not sound poetry in the same way as the above, but we are on ubu as well)
under recent additions
clairaudient