Does anyone know if there is a CD website that states the category of music of the singer/artist?

For example: Diana Krall - Jazz

Theres a pretty good website for music artist info and their history etc.. check it out. allmusic.com

hope this helps

well itunes and windows media player both do it automatically

gracenote.com, and cddb (cd database) do that well too,

Try CDNow.com. You can get reviews and sample pieces from albums. also helps to find artists of a similar genre.