Thanks for the link but the girl on the website looks way too young.
The one with Stevie looked a lot older and had been ridden hard and hung up wet. Also, her enunciation - if you closed you eyes, you'd swear it was a black female singer.
The other person I saw listed with him was India Arie. Since I didn't see it, that's all I've got for guesses.
http://www.askmen.com/women/singer_100/129_india_arie.html