I wouldn't even bother making a special trip to a Ducati dealer for a start. As others have said, your friendly neighbourhood key-cutter may well have a suitable blank; I got a key cut for my 750SS just round the corner.
My bike (996s) only came with one key - my local shoe repairers/ key cutters sent off for kawasaki blank keys and 2 days later cut me a couple of spares.