In the popular wine-touring regions (Napa, Bordeaux, Champagne and even Long Island during peak tourist season), strangers are dispatched on group tours with summer interns as their guides. Every tour is the same: These are the tanks where we ferment our grapes; these are the barrels where we age our reserve wines; now let's taste some of our cheapest ones. Questions are met with a blank stare, and tasting opportunities are very limited.
But it doesn't take all that much effort to take a private tour, guided by the winemaker, perhaps, or a senior member of the staff, and to get much, much more out of a winery visit than the average tourist does.
First, never go unannounced. It's essential that you make some sort of connection with the winemaker, even if it's just in the form of a friendly fax saying that you admire his wines and buy them frequently.
It's even better to use an industry connection, and you'd be surprised how many such connections you already have: For example, if you buy most of your wine from a particular store, you have an industry connection! Next time you buy a case, tell the proprietor you're going to Napa (or wherever) next month and ask if he has any contacts out there. Ditto if you frequent a restaurant with a sommelier. And, when you're finally in the region, be sure to talk to the concierge or proprietor of your hotel. For example, if you're a guest at Les Crayeres in Reims, France, and you want to visit the Pommery Champagne house across the road, a quick call from your concierge to Pommery is all it takes to get you a VIP tour and tasting. Second, always visit off-peak. The harvest -- late summer and early autumn (in the northern hemisphere, at least) -- is the busiest time of the year at most wineries. At any other time of year, winemakers may be more inclined to chat.
Third, pace yourself. Don't try to pack too many visits into one day, especially when you have appointments. You never know how long a visit may run, especially if there's chemistry between you and the winemaker. (I've had visits that started in the morning and continued well into the night.) And travel can take a long time (you're in farm country -- distances can be vast). Two or three appointments a day are plenty.
Finally, if you taste something you like, ask whether it is available in your local market. If so, get the name of the local distributor and ask your wine merchant to acquire it for you once you return home. Some wineries can also ship directly to your home via Federal Express (state laws vary on this).