If you've never heard of go, you are not alone. The game is very popular in Asia. There are professional go players who have the same name recognition that professional golf players have over here in the States. There are many tournaments, and the top players can make alot of money if they win.
You can play go realtime online at The Internet Go Server (IGS)
Or if you prefer to play face to face, check out the SF Bay Area's go scene.