Some things to consider:
Have you visited before?
If you're new to the area and maybe fairly new to wine (not a wine geek) the choices are different than for the person who makes a yearly excursion to the area to buy wines to age at home.
If you are new to California wine tasting you may want to check out a couple of the more famous places such as Mondavi, Beringer, Chateau St. Jean or Sebastiani.
Typically visitors do something like this: First trip to the wine county means visiting the big names in Napa Valley. Second trip they go to Sonoma for somewhat lesser known stops. About the third trip they are looking for the out-of-the-way places.
|Too many choices!|
When are you visiting?
If you'll be in the area, especially Napa Valley, in peak tourist season there will be big crowds and lots of traffic. If you're not willing to deal with that stick with more out-of-the-way places. That is, don't go to Mondavi, Beringer, Chateau St. Jean, or Sebastiani.
Where will you be staying?
Plan your driving distances. For instance, the travel time between Bella Winery in Dry Creek Valley and Viansa Winery in Carneros (both are in Sonoma County) is about an hour and a quarter. Plan your lodging central to the areas you want to visit.
What do you like to drink?
Chardonnay, Cabernet, anything red, ABC (anything but Chardonnay)?
Certain areas specialize in certain varietals. Maybe you are looking to discover something new like sampling a lot of Zinfandels or sparkling wines. Maybe you have a favorite wine at home, say Sonoma-Cutrer Chardonnay, and you want to get an appointment to see where it's made.
Wine tasting at many different wineries is a great way to break down any personal prejudices such as, "I only drink sweet wines" or "I only drink reds" or "Anything under $15 isn't drinkable" or "California Pinot Noir is crap."
Use this opportunity to discover something new about wine!
How much are you willing to spend on a bottle?
If your limit is 25 bucks then a private appointment at Diamond Creek where the least expensive wine is $150 is a waste of your time and theirs. This doesn't mean you shouldn't try more expensive wine than you buy at home. If you've never had a $75 Cab you might as well sample a couple to see if there really is a difference with the $20 ones you normally drink.
What's your tasting budget?
While we're talking about money you can easily spend $25 per tasting fee in Napa. If you do that for you and your Significant Other and plan five stops a day for three days, well, that is getting into real money. Sonoma County is cheaper and most Sonoma wineries will not charge you to taste if you buy something. There are a number of wineries in Sonoma that don't charge for tasting, there are fewer in Napa that don't.
Any other special things you are looking for?
Views, picnicking, wines you can't find at home, wines you can find at home, small family wineries, large wineries, tours, art? Would you like to have a wine tasting in a cave or tasting from barrels? Tours can be broken down into production (how wine is made), caves, or vineyard tours.
Google is your friend. Just be aware there are sites that wineries pay to advertise with and will list ones paying the most at the top under a title something like, "Featured Wineries." Some less commercial web sites are:
So what if you are really new to this and don't have an idea of what or where you want to visit?
First, pick a central area to the wine regions of interest for your lodging. Next, plan on visiting a couple well-known wineries that look interesting plus pick one nearby that is small and family-owned to get a contrast. Then you can plan on-the-fly from there.
If you have several days plan on a day in Napa, a day in Sonoma then leave the rest of the time open to go back to the area you'd like to see more of.
Enjoy your visit!