Unlockable: Characters and Stages
Alien Doctor - Complete Story Mode on Normal difficulty.
Australian Cop - Complete every Classic Mode goal on Sick difficulty.
Boat Captain - Complete Story Mode on Normal difficulty.
Bratwurst Vendor - Complete every Classic Mode goal on Sick difficulty.
Canada - Tony Hawk 3 Stage - Complete Story Mode on Normal difficulty.
Corn Vendor - Complete every Classic Mode goal on Sick difficulty.
German Cop - Complete every Classic Mode goal on Sick difficulty.
German Drunk - Complete every Classic Mode goal on Sick difficulty.
Horn Player - Complete every Classic Mode goal on Sick difficulty.
Lost Soul 1 - Complete Story Mode on Normal difficulty.
Lost Soul 2 - Complete every Classic Mode goal on Sick difficulty.
Metal Detector Man - Complete every Classic Mode goal on Sick difficulty.
Neversoft Video - Complete every Classic Mode goal on any difficulty.
Paulie Ryan - Complete Story Mode on Normal difficult.
Pirate - Complete every Classic Mode goal on Sick difficulty.
Pro Skater Stage - Complete Story Mode on Normal difficulty.
School - Tony Hawk 1 Stage - Complete Story Mode on Normal difficult.
Shrek - Complete Story Mode on Easy difficulty.
Skatopia Punk - Complete every Classic Mode goal on Sick difficulty.
Space Monkey - Complete Story Mode on Easy difficulty.
The Hand - Complete Story Mode on Normal difficulty.
Zombie 2 - Complete every Classic Mode goal on Sick difficulty.

Cheat Perfect Rails
Just type in "tightrope" and you will have the option of perfect rails in the game.