There are two shop manuals, one for the engine and one for the "chassis." They have Ducati part numbers and unless they have been discontinued you can order the CDs from any dealer. There is also a parts manual. These are ALL the same manuals that Ducati dealers use.
I bought the CDs right after I bought my bike. A couple of years later I bought out a closed dealer's D16 inventory and part of what I got were the same two shop manual CDs, both showing signs of wear like they had been used in the workshop.
There is no super double-secret manual printed on the hymens of virgin nuns. There may be a few service bulletins. I wouldn't mind a set of those. (Not talking about the recall notices.)