I also have no connections to major sports sites and such, but I've also found it effective to just blog/review BuzzerBeater on smaller sites and then promote these articles about Buzzerbeater.
Here is a post I recently wrote:
http://www.ggmonster.com/archives/monthly/2010/05/buzzerb...If you see on the bottom, there are many tools for spreading the word (facebook, twitter, stumbleupon, digg, etc.). I would also encourage anyone who uses any of these tools to promote the main site as well, I've had some success with that.