Beginners Guide to NXT Sumo:
Robot sumo is one of the fastest growing sports around. Now if you own a LEGO MINDSTORMS NXT, you can join in as well.
If you still don't feel the urge to get down to designing your own Sumo robot that is going to kick butt in the sumo ring against contestants all over the world, then this might help. This beginners Guide also has a video that walks you through getting your model ready for NXTLog in five simple steps.
Beginers Sumo Guide on LEGO web site.
If you checkout the five step video, you would notice a small clip of a Sumo robot in action with another robot. If you want to see the complete battle, check out this YouTube video:
And you still have a few days left if you have not started your Sumo robot. Good luck!