I live there, but haven't gone wine tasting in years. We used to enjoy it a lot. Do the Sonoma wineries,
unlike Napa, still
not charge for tasting?
Napa is sort of the Disney of wine experiences, so expensive, and basically "stand in line," as they are all along the same road. Sonoma County has several different areas, but you won't be in some fairy tale wine country setting altogether, just driving in and out from winery areas through "regular people" areas. The SR Hilton is not right near any wineries.
Basically you would go to the Russian River area in West County, the Alexander Valley/Dry Creek area near Healdsburg, or the Valley of the Moon area out towards Sonoma. Then there is the Carneros region that straddles Sonoma and Napa Counties. There are way too many wineries to do them all, so it is best if you do some research and decide what it is you are looking for - a celebrated wine or varietal, or a special tour or scenery, or what have you.
Or go to Napa for the imposing, fake chateau-looking wineries where everything is high-falutin' and you might have trouble getting ressies in the expensive restaurants. It will be more like Disney and may conform more to an ideal of a wine country vacation (plus they have fancy expensive spas, too, for instance in Calistoga)