[Orb] orb DVD tree

I recently did what I could to put together my entire 30gb Orb collection onto 7 4.5gb DVD's using NeroBackITup. Burning copies of this for more than just a couple of people would be a huge pain in the ass, but it could be done. A lot of what I have are duplicates, but 90% is sorted nonetheless. The ORB DVD image is in there, also. How was the MP3 CD Tree done the last time?