My wife and some friends went down to Tokyo several years ago to watch live Sumo. It was absolutely a great time. We cheered for our favorite rikishi, tried to figure out what various moves were called, drank a lot of beer, and ate squid jerky. Good times.
One highlight for my wife was getting to meet some of the wrestlers she had seen on t.v. when she was a girl. After retiring, the wrestlers stayed in the organization training younger guys and the like and if you go in early, you can often find them just hanging around and have a bit of a chat.
And make sure to get a handprint from the rikishi. They look great up on the wall.

