snypz,
You will find 253,649 arguements on the topic of what equipment does the Neptunes use. I for one, actually saw two short clips of the Neptunes in the studio. They both were ran as a special for MTV during the last two Video Music Awards. Basically they have a number of boards and guitars, and I know that the first instrument that they learned was the sax. But don't take my word for. Try to see if MTV still has the clips on the website, if not call them and ask for a video, matter of fact if you are able to see the one from two years ago, you will also get clips of Timbaland, P. Diddy, and Jermaine Dupri in the studio.