How to invite a friend in online Mode (PC) ?

Is there any option to invite a friend in the game ?? I can't see anything about it... or it is impossible to do with 2k12 ?
What about Online Association, why commissioner have no options to change sliders or other important league things, even reset the game..

1. It seems like you can do this when the homepage (nba2k.com) goes online.
2. because 2k guys just care about nba greatest shit -.-