Hi Tim - never made it myself but I did find this one previous discussions about making it from grapes that might be of some help to you. They recommend using brewer's yeast and it is really cheap. NOW brand by is $8 on amazon and about the same at Walmart.

http://forums.gardenweb.com/discussions/1496544/is-this-an-acceptable-way-to-make-grape-vinegar?n=6

Dave

PS: you could buy lots of vinegar for $20 :-)

Thank you