Enter the following as your Created Skater's name...
Select ''Cheat Codes'' in the Options Menu on the title screen and enter the following:
To do this, go to either Career Mode, Single Session, or Free Skate, on the skater selection screen, Highlight Steve Caballero but DON'T go to A level, instead, go to the credits and look on the ground of the generic skaters and you see Steve Caballero's guitar on the ground.
Earn cash in the game to buy these unlockables.