Stadium Passwords 
On the matchup screen of a Preseason game, press SQUARE to go to Preseason 
Options. Press L1 to Toggle the Home Team as defaut stadium. Then scroll to the 
stadium you want to unlock (their text is red). Enter the following codes to unlock 
stadium: 

Stadium - Password 
Old Carolina - CAROL  
Good Ol' Days - SEPLA TONE  
Galactic - GOVT OWNED  
Old Denver - 5280 FEET  
2050 - LIGHT YEAR 
Old Detroit - AUTOMOBILES  
Unknown - EMERALD 
Old Chicago - WINDY CITY  
Old Los Angeles - ANGELS  
Old Miami - ORANGES 
Old New England - SALEM  
Graveyard - RISING 
Space - LUNAR 
Pop Warner mode - MUNCHKINS  

Unlock Old L.A. Stadium:
On the matchup screen of a pre-season game, press SQUARE to go to Options. 
Press L1 to Toggle the Home Team as the default stadium. Then scroll to the 
stadiums you want to unlock. Enter angels to unlock this stadium.  

Low salary cap:
Players might want $10.00(TEN MILLION) a year but create a player and he will 
want about 6-9 million.

Win a game:
Lower the penalties and everytime you make a touchdown, you can do little baby 
onsides.

Get sweet players:
Create a player, then you can trade him or them for player(s) you want. 

Example: 

QB #18 Peyton Manning 94 
for QB #13 Dan Marino 94 

Usually they'll say yes, but i never got Peyton Manning.