http://www.myspace.com/vanessamarquez
http://en.wikipedia.org/wiki/Vanessa_Marquez_(singer)
Vanessa Marquez, sang the girl's parts in Rock Your Body and did a few songs with Pharrell Williams and co. while she was signed to his label.
She left in 2005 when her contract ran out and has been unsigned since.
Some of her stuff is actually very good.