I hope it's okay if I post here even though I'm not American ...
But yes, it's a good idea. It's not very difficult to create a flier ... and this communication tool is kind of cheap. Indeed, anyone can print on a piece of paper and broadcast the fliers anywhere : American, Brazilian, French, Thai, Indian and so on, each country will be able to promote BuzzerBeater in an off-line aspect. As matter of course as long as they respect legal conditions.
I know that the BB-community counts several talented graphic artist, why don't you create a competition design with two separated aspect :
1) The message
Ex : Never dreamed of beating the buzzer like the greatest basketball players of the history ?
Join Buzzerbeater, the biggest FREE online basketball management game ...
... And help the American national team to the road to the World Cup !
2) The design
Ex : I've no example to give as I'm the worst graphic artist that ever existed on earth !
What do you guys think ?