having trouble figuring out how to install mods

[nolushhere]

So I bought the game at the store, installed it, and it seems obviously you gotta have steam on to play it.

Cause it basically brought up steam and installed the game. Problem is, I only see nba 2k9 in my steam folder now, so Im trying to figure out how to install rosters, shoe sets, and slider sets, and am totally unsure where to extract those things too.

Any help would be appreciated.