This is easy, Pause the game and Hold L1 And Press X, Circle, Square, Triangle, Up.
How to get Rodney, Mullen, Eric Koston, Busky Lasek:
Complete the game with all 8 characters and get all the objectives of every skater & the secret boards & you will unlock RODNEY MULLEN, BUSKY LASKEY, &ERIC KOSTON.
Secret Mining Cave:
Beat the game, and the last level is the ancient ruins. Go up the ramp ahead when you start, and bare right. You should go in a mineing cave.
How Get Levels Faster:
When you get to the level do just the right amount of missons to get to the next level. I got to the last level in 2 hours
Special Tricks:
Air Special:
Up,Up,circle
Flip Special:
Up,Up, Square
Grab Special:
Up,Up,R1
Player's Max Special:
Triangle, Triangle (every player has a different max special)