Well, the whole "not having an xbox 360" thing is a problem, but if you get one, hooking it up to the internet is easy. It has an ethernet jack in it, just like any computer does. You just plug it into your router or modem.
I understand that this is an expensive way to have fun, and apologize to the guys who can't drop $500 for xbox + xbox live + nba 2k7. Maybe you can get one in time for Season 2, around the all star break.