You mean SEO, right?
As a matter of fact, BB does very well in terms of SEO. That's how I managed to find BB, afterall. Type Basketball Manager Sim and BB comes 3rd, after a single player game and a site with reviews. In just "Basketball Manager" search, it's 4th or 5th. So, I don't think there will be any huge improvement if they throw money into SEO or Google ads.
Facebook is the way to go: Target people who like Basketball, I would narrow the age field too, in order not to target very young persons (as I think most managers in here are around their 30s) to fit the age with the pace of the game and they seem more willing to be supporters, I'd even target based on their tech behaviour.
As a plus, I'd start issuing press releases to baskeball sites/blogs/forums too. Nothing special here, but having a site myself (irrelevant to basketball), I know that most sites appreciate free content. A banner exchange proposition to some of these sites/blogs/forum wouldn't hurt either.