Go to options screen and select "Codes". Enter the following codes:
Note: You can disable the effect,  if you repeat the code.

Easy alleyoops - IMFLYING
Unlimited turbo - HOTSAUCE
Easy three pointers - RAINING3S
Small players - MOONCHY
Unlimited created player points - UNLIMITED
Accept all trades - ARELESS
Chicago Skyline stadium - DOWNTOWN
ABA ball - FUNKY
WNBA ball - CHANGEBALL
Xbox ball - XSNSPORTS
Beachball - CONCERTSPIKE
Soccer ball - DIEGO
Volleyball - BAMBIBOOM
8 ball - CHALK
Bonus players - ICECREAM
Note: You may now enter one of the bonus player's  names at the player 
creation screen to unlock that person.