Tokyo Sumo Stable Tours for a Memorable Japan Experience
If you are interested in visiting a Sumo stable and watching the wrestlers train for the day, there a many many opportunities available to do so.
Most stable now have their own websites and I am guessing that you the visit may have a particular wrestler that you are fond of a know the name of the stable he belongs to.
Do a search for the stable online and you may need a friend with some Japanese knowledge to assist you in reading the info.
Here is a site with some English information as well: http://www.mytokyoguide.com/sumo-training-tours
It is the most exciting experience ever to see the young wrestlers training and you will leave with a greater appreciation of what it takes to become a Real Sumo Wrestlers.