There are tremendous backgammon resources available online, no matter what your level of interest in the game. You can play, study, read backgammon related humor and stories, find out about "real life" players and clubs, buy and sell backgammon merchandise, and more.
Below are links to several of the best places for accessing these resources. Much of the best online backgammon content is located at these sites, and from these sites you can get to pretty much everywhere else. Have fun!