@Rampant Spaniel...
You just have to know where to look to find decent wine in the US... Start you tour in little ol' Napa Valley. Napa Valley has over 400 wineries, some very small to some VERY LARGE... Small ones tend to be the better wines, but even the big boys have some decent fermented grape juice. And do they love to experiment... whether with grapes or specific vineyards, or blending a wine with some small doses of different varietals to produce some fantastic wines. Some are available ONLY at the winery, some are available ONLY by mail order. Some, like Silver Oak Cellars, sell out at the release party, and they only have enough left to sample and sell at the winery, and if you're lucky, you can find their releases at a few high-end purveyors, or maybe your favorite restaurant, like The French Laundry. One of the hardest to get is Screaming Eagle... They offer no tours or tastings at the winery (it's not even listed in the phone book, and only a few lucky limousine drivers know where the winery is located)... the only way you can get Screaming Eagle is by mail order, IF you're on the mailing list, and there's a LONG waiting list to get on the mailing list... of course they also sell out every year, and I have never been able to get a bottle, even a $800 (or more) each.
Paris, 'cause if I had her money, I could afford to get a bottle of Screaming Eagle, or maybe Michael Mondavi's Spellbound, at about $40 a bottle.