I have searched around for a sports betting mod like the vBookie in vBulletin but have found none so far.
The ones that got closest were the Sportsbook
and Ultimate Points
But ultimate points has not got a betting system and Sportsbook's download link is not working, and the author has also been absent for a while, i suppose it would be declared abandoned soon.
If there can be a betting mod, it would do a lot of good for the sports related forums. Or atleast if some one would fix that link for Sportsbook