Use this link or this link and plan your own mini-wine tour. Make sure you don’t over plan. Personally, I think 5-6 wineries are about right. Too many wineries can cloud your reasoning and create too many opportunities for that friend who loves to take awkward photos and then posts them on Facebook.
When you’re done with your tour, finish your day with a nice meal at one of these local restaurants. Most places don’t mind if you bring one of those bottles you purchased during your tour--but call ahead and ask first. There may be an uncorking fee.