Amber Manfree | Oct 27, 2015..one more find I just turned up - a map designed for wine makers that shows locations of vineyards with grapes available for purchase. Not directly helpful in any way that's obvious, but a really interesting project nonetheless.
EveryVine.com Napa region online map
Bill Hocker adds:
The hoard of information given each and every vineyard block in the county is mind-numbing. Wine freak meets database freak.