Change Songs:
Press R + X to go forward or L + X to go back to access all songs.
Unlimited Creation Points:
Go to "Rosters" then choose "Edit Player". Select the player you want to be rated 99, go into his attributes and increase all of his stats.
Unlock Mummies Team:
Use a Memory card that has a saved game file from an EA Sports Racing Game
Unlock Dodge City Stadium:
Use a Memory card that has a saved game file from an EA Sports Football Game
Unlock Marshals Team:
Use a Memory card that has a saved game file from an EA Sports Football Game
Unlock Nile High Stadium:
Use a Memory card that has a saved game file from an EA Sports Racing Game