Dear drdave,
Unfortunately I know nothing about making vinegar from scratch. To my way of thinking, vinegar is one of those things I would rather buy than make. I am just not going to be able to make it very well.
I do make the Japanese ‘drink’ vinegar with ume, peaches, etc. I am actually just about to make some with Japanese lemons. However, this just involves macerating the fruit in vinegar and sugar.
I did find this REALLY detailed post on how to make persimmon vinegar.
http://tkksi.web.fc2.com/kitchen/autumn/kakisu.htm
Now, this would be really interesting to make. And, the ‘starter’ is naturally occurring on the skins of the persimmons.
I have been able to get into a lot of sake, shoyu and miso breweries in Japan. I just cold call them and tell them what I am interested in. They are usually willing to take a little time to give you a tour and let you see the production process. You might try that.