The Beringer winery is my favorite. Nice grounds, great architecture, and decent wines.

your question is very timely.
last sunday's chronicle had an article about wineries and wine tasting.
sorry i don't know how to do the small url.
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2009/03/22/TRVL16BUSQ.DTL&hw=wineries&sn=001&sc=1000

We loved Castello di Amoroso - beautiful castle - the tour and tasting were great.

A current thread on this topic: http://www.fodors.com/community/united-states/tasting-res-needed-in-napa-this-april.cfm

Do you want the can't miss wines or the most interesting wineries?

For wineries, Sterling (near Calistoga) is great because you take the aerial tram from the parking lot to the winery and you have great vies of Napa Valley.
Domain Chandon just outsideof Yountville has an interesting self-guided tour about sparkling wine.
Artesa, between Napa and Sonoma, is on top of a hill and on a clear day you can see all the way to the San Franciso Bay.
and Beringer has interesting grounds as noted above.

BUT, if it's the wine you're after, my money goes to
Rombauer off Silvarado Trail, Sequoia Grove and Schramsburg (need reservations in advance $20 per person).
Of course, the wine is a very individual thing and many others will have much different, but equally valid preferences based on their tastes buds.
ENJOY!

Good recommendations above. Mumm is very nice too, especially if you enjoy sparkling wine. It's on Silverado Trail, which is on the east side of the valley (Route 29 is on the west). They have a nice outdoor patio with great vineyard views, and the tasting consists of a flight of 3 or 4 wines served to you on the patio.

Chateau Montelena, Castello di Amerosa and Sterling in the Calistoga area. We LOVED Ferrari-Carano in Healdsburg, gorgeous grounds and gardens and very good wines. Kendall-Jackson has a tasting room on the Plaza, we did the Reserve tasting there and purchased a bottle of the Reserve Zin that we took to dinner at The Lakefront restaurant in Mammoth this past weekend. ***kim***

My favorites were Beringer (mentioned above) and Mondavi.
Happy tasting!

Doing some research. Found this site that might be helpful:

http://winerytips.com/

Click on the highlighted wineries and takes you to their site.

I agree with the Schramsberg recommendation. Great tour and great wine.

Pine Ridge, Quentessa, and Sterling. Make sure you drive along the Silverado Trail.

I'm seconding Schramsberg and Mumm for sparkling. Both had very nice tours.

After a bit of an absence, I still owe several trip reports - and one on my trip to Napa in November of 08 ! I hope to get it together next week: in the meantime, wineries we visited that I would highly recommend - Quintessa, (and I believe you need reservations and there is a fee) - Schramsberg was a fun tour - with a nice tasting of their champagne and wine -
Chappellet was one of my favorites, with a fantastic view - Larkmead, Barnettt, Regusci (the latter no tour , but also great olive oil) and the view from Pride Mountain is breathtaking -
Most required reservation and possibly fee, don't mean to sound vague about it, but we had a driver who arranged all reservations and tours and/or tastings or our concierge did a few for us and fees were waived - our favorite wines were at Quintessa, Chappellet, Larkmead, ....oh heck, we ended up buying at all of them, also loved Regusci, Darioush...and I'm probably leaving a few out --- heck, guess we liked them all !! - Chateau Montelena we did on our own one morning and walked the grounds, which I thought were ok, but it was fun to then watch the movie bottleshock ( even though I understand it wasn't even filmed in Napa, but Sonoma even though it is about a Napa wine from Chateau Montelena, there were shots of the winery)

This only makes me more motivated to get my trip report up about the wineries, restaurants, etc...... after we get Easter dinner out of the way tomorrow and the company leaves on Monday......

Gosh yes, I was there two weeks ago (for the sixth time) and I haven't written my trip report either. No trip to Napa is complete without a side trip to Sonoma, but I am prejudiced. Artesa is gorgeous. Hess is a drive , but the grounds and the jaw dropping art gallery are amazing. There are many nice, smaller places on the Silverado Trail. Zahtila, William Harrison, Steltzner, Dutch Henry (a hoot). Bennett Lane has great wines. Peju was a nice tasting. For a fun tour, Frog's Leap. Unpretentious. Touristy, but beautiful and truly unique is Opus One. They do everything by hand. Schedule a tour in advance.

We used to visit the Napa wineries but the prices have escalated in the past few years. We now visit the Sonoma wineries where many are free tasting or a small charge refundable upon purchase. Was there last week and had a great times. There is a wonderful Italian restaurant in downtown Santa Rosa.
Castello di Amoroso was $25 for the tour and wine tasting. It is a beautiful location
Sterling is fun to go to for the view but don't care for the wine. I agree that Rombauer is the best.
We like the Ferrari winery in Dry Creek. http://www.ferrari-carano.com/ and the Pedroncelli winery http://www.pedroncelli.com/about/index.asp

My favorites Napa & Sonoma are:
Artesa
Domaine Carneros
Bouchaine
Sterling (nothing else like their Sky Tram)
Castello di Amorosa (takes you back in time with a exact replica of castle complete with torture chamber etc)
Rutherford Hill (caves)
Hall (has two locations for two different experiences)
V. Sattui (there is no better picnic spot)

Sonoma
Kunde
Benziger (the best tours)
Arrowood
Simi
Schug (can quite possibly run into the owner and thats treat)
Francis Ford Coppola winery (this used to be called Rosso & Bianco)

Always before going, I often visit a local site http://www.econcierges.com to print FREE tasting offers and discounts on spas, hotels and restaurants. In this economy any deals help a LOT!!!!

We liked Beringer, Mondavi, and Sterling.

bookmarking

A terrific winery in nearby Somoma is Benziger Family Winery. Browse the beautiful grounds by taking a nice, self-guided walk or hop on their fun, Biodynamic Vineyard Tram Tour.

When in Napa, a "must" is the Napa Valley Wine Train.
http://www.thelifeofluxury.com/enjoy-wine-country-on-the-napa-valley-wine-train/

I second Hess, on the top of Mount Veeder. Excellent wine and a first class art museum, IMO, featuring a huge Frank Stella metal collage. Worth the trip.

I would second Chappelet and Artesa for both the views and the wine- very nice. If you are into Ridge, make a pilgrimage to their winery / tasting room north of Santa Rosa. Worth the trip. We also made a reservation for Caymus-good because the Wagners were one of the original Napa wine families.

We booked our entire trip through Jackie Richmond at Wine Country Concierge- worth every single penny.

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