There are more and more wine courses being offered all over the country. In the long run, though, the only way to really learn to appreciate wine is by drinking it. Find a good, patient wine merchant — there are many of them out there — and buy a case of wine. Set yourself a price limit — say, $100 — and tell the merchant you want a mixed case of wine from all over that will not exceed that limit. Put the wines in a dark place with a moderate, constant temperature, like the bottom of your closet, and drink up. Try to take some notes on the ones you like, especially the ones you might want to try again. When those are gone, buy another mixed case of wines that are new to you.
Now is a great time to be discovering wine because there are so many reasonably priced, tasty wines available from all over the world. Enjoy the journey!