We spent a few days in Paso Robles last month (yes, while it was crazy hot!
) and had fun exploring the bounty of wineries and tasting some great wines. I just happened to notice that the weekend of the NorCal Rally Paso Robles is hosting their annual "Harvest Wine Tour" where most of the wineries offer tours, special tastings, and events like hayrides, grape stomping, and art shows. Sounds like it will be a fun weekend in the wine country!
More info on the harvest:
http://www.pasowine.com/events/harvest.php
Winery map:
http://www.pasowine.com/wineries/map.php