We've set up a private group at Yahoo for the NCAA Tournament. First, visit here to get signed in. Then, select "Join Private Group." Our group number is 50068, and the password is J&B. That should be all you need!
With a limit of 50 people per group, I've created three more groups, Duke Basketball Report II, III, and IV. The password is the same for each, the group numbers are 54523, 54525, and 54527 respectively.