His music is not what strict die-hard classical musicians consider "serious classical" but it is definitely a genre in its own right. Check out his music on YouTube.
http://www.youtube.com/watch?v=9wxrB41PMhw&feature=colike
http://www.youtube.com/watch?v=VlvBHJAdQF0&feature=colike
http://www.youtube.com/watch?v=641xeu4Xo60&feature=colike
http://www.youtube.com/watch?v=-HP_BR_rC6k&feature=colike
http://www.youtube.com/watch?v=atSLxdAVSzk&feature=colike
Bonus - To purchase and download scores, see:
http://www.musicnotes.com/features/artists/davidlanz/