Astor Wine & Spirits Tastings
Astor Wine & Spirits is quite possible the best wine/liquor store in the city. The BREADTH of that place is truly incredible (and they have the 700ml Grand Marnier that I need for big batches of spicy margs). They also do free tastings, which you can find on their events page. There are multiple a week lasting around 2-3 hours and after tasting, you can go enjoy a 20% discount off wine they poured. Boom.
If you're looking for a little bit more, they also have various events per month focusing on a wide variety of wines and spirits (e.g., "Piedmont and Beyond", "Whiskey Smackdown"). These usually include a welcome drink, ~6ish tastings, small food pairings, and palate cleansing bread. These last around two hours and are taught by the professionals at Astor Center and are around $90/ticket.