Here's some various links related to the 9000 Pro I've collected:

Yamaha's 9000 Pro Support Page: http://www.yamaha.com/ycaservice/group019/fgrop019.htm

Kraft Music: the Kaces KKP-11KB fits the 9000 Pro: http://www.kraftmusic.com/catalog/accessories/keyboardcases/index.asp?product=1889

Review of the PLG150-PF Piano Expansion board: http://www.computermusic.co.uk/reviews/plg150pf/plg150pf.asp

Review of the 9000 Pro by EM: http://industryclick.com/magazinearticle...46652&siteid=15

The USB mod for the 9000 Pro: http://www.musitronics.de/info-e/USB-9000-e.html