My partner and I attended a fantastic 2 hour wine tasting course yesterday at the Majestic Wines store in High Wycombe, completely free of charge!
This is nationwide (click on the link to locate your nearest store) and as far as I'm aware there are several dates available over the next couple of months. When I called to book mine the store manager said she had 3 more dates available til around April.
We learned all about red and white wines, champagne and how to match your wine with food. Very friendly host and lots of nibbles to munch on during the session too. At the end of it we got a 10% voucher to use in their stores.
Fortunately there was no obligation to spit ;)