Need For Speed Underground cheats and cheat codes for Gamecube

Unlock all drift tracks:
Press Left(4 times), Right, X, R, Y at the main menu. 

Unlock all sprint tracks:
Press Up, X(3 times), R, Down(3 times) at the main menu. 

Drift physics for all cars:
Press R, Up(3 times), Down(3 times), L at the main menu. 

Unlock all circuit tracks:
Press Down, R(3 times), X(3 times), Z at the main menu. 

Unlock all drag tracks:
Press Right, Z, Left, R, Z, L, Y, X at the main menu. 

All visual upgrades:
Finish all missions in underground mode. 

Easy drift points:
Turn off the stability control by going into options and selecting "Car". 
This will make the car drift easier.

Get Samanthas Honda Civic
Reach at least 2,000,000 style points

Unlock 10 New Rides
Reach at least 4 million style points.
Nism Nissan Sentra, Acura Integra Type-R, Petey Pablos car, Samanthas car, Rob 
Zombies car, Mystikals car, Lostprophets Nissan Skyline, Junkman's Honda Civic, 
Melissas Nissan 350Z, Eddies Nissan Skyline and a few more if you continue on 
to 5 million style points.