I usually look for something local to do. I used to research sites such as Chow forums, road food and occasionally DDD but those sites are outdated now and there isn't much new or reliable content. Yelp and Trip Advisor are not reliable either. I also used to look on Groupon and Living Social, back when they actually had real tastings and cool tours. They sometimes still do, but you almost have to be a local to sort out which one is a real tasting at a decent place rather than a badly advertised singles event at a shady bar or in someone's garage.

I had excellent cooking classes in Phuket, Bangkok and Munich, attended a few good cooking demos at the Intercontinental Grand Stanford in Hong Kong (International Chef Series.)

For wine tours, Napa was ok. The Niagara Peninsula (Canada) and the Finger Lakes area also offer a good concentration of wineries, breweries, fromageries and distilleries. In some areas, there are tours that allow you to pick your own wineries/breweries within reason.

Beer tours varied from being shuttled on a bus with drunk frat bros to aspiring micro-brewers with analytical paperwork on ABV and hop variety and provenance.