This is a tour I've taken two times, last time 4 years ago. It takes off from Guadalajara (GDL), in the past it'd go to Tequila and then to Sauza, but since then it has changed and now goes to Casa Herradura. You'd need to be in GDL to take it, it starts off relatively early in the morning from the old train station in a comfy train, margaritas and mariachis right from the start. I can't say much about the Herradura part of the trip as I have only been there on a fast trip, I can assure you that the Herradura installations are very nice looking, old-fashioned. They'll show you the tequila process and feed you lunch, there must be a museum and show too, I imagine the official site explains it all.
When we took it, once with my wife another with her family, everyone enjoyed it a lot. Planning to take it again so my child can travel on a train, which he is impressed by.
I imagine a trip like this would require skipping two days from Vallarta, one to travel to GDL (5 hours distance by bus, recommendable to take a plane better, around 200 USD roundtrip) and stay at a hotel and leave early to the station for the tour, upon return, either stay one more night and enjoy the city again or take off to Vallarta by bus or plane.
I don't think there are package trips that include the Tequila Express tour from Vallarta, maybe I'm wrong... maybe someone else can help us out on that.
If you already have a trip planned to GDL then I can fully recommend the tour, but if you are in PVR and are thinking of day-trip tours, then the Tequila Express is too much of a hassle, expensive and time consuming (plus logistically a bit complicated), only for experienced travelers.
Tequila Express: http://www.tequilaexpress.com.mx/
(the English version didn't load when I tried...)
Herradura: http://www.herradura.com.mx/age.aspx?Re ... fault.aspx
Here's the itinerary: http://www.tequilaexpress.com.mx/home_recorrido.htm
- you'll notice you get there at 10AM and return around 8PM, so a plane trip back to Vallarta might be cutting it a bit close...