Specifically engine parts? I managed to crack an engine case cover while trying to remove it to swap out for a lightweight flywheel. (the shifter shaft is the culprit and the thing pulling off at an angle)
Any websites allow you to buy OEM parts like BikeBandit?
I think you can buy from some dealers online, perhaps Ducati Omaha.
Ducati Seattle is a very good one to buy from, they stock a lot of parts.
Honestly, Ebay or our classifieds are gonna be a lot cheaper.