There are some sample videos for some of the music.
http://www.youtube.com/watch?v=wfy-kQwTElU
http://www.youtube.com/watch?v=SVsw34Dk8l8
On the second video, two of the tracks have vocals by "Emi Evance." I'm sure it's a typo, but I asked her to be certain, but it does sound like her.
EDIT: It is her, so I've added her to the performers.