For these tricks go the the pause screen. Hold down the L button and then hit the following buttons:

Perfect Balance - C-up, C-right, Left, C-right, Right, Up, Down.
Restart Locations - C-Left, C-Right, C-Down, Up, Down.
10X Trick Points - Down, Right, Up, Right, Up, Left, C-Left.
Fast Motion - Right, Up, Down, Down, Up, Down.
Slow Motion - Down, Down, C-Up, C-Right, Left.
Fast Tricks - C-Up, Left, C-Down, C-Down, Up, Down, Right.
Get All Tapes - C-Right, Left, Up, C-Up, C-Up, Right, Down, Up.
Stats at 10 - C-Up, C-Left, Left, Up, C-Down.
Stats at 13 - C-Up, C-Left, Left, Up, Down.
High Speed - C-Up, Left, C-Down, C-Down, Up, Down, Right.

Play as Officer Dick - Collect all thirty tapes with any character in career mode to unlock Officer Dick.

Play as Private Carrera - When playing the game with Officer Dick, go to the pause screen. Then hold L1 and press C-Left, C-Down, C-Right, C-Down, Up, Right, Left. Unlike the other cheats, the screen will not shake when you enter the code. When you exit and go to select your character again, Private Carrera will appear in place of Officer Dick.

Get Private Carrera without getting Officer Dick - Get a tape (anywhere) and then do the 30 tapes code (Hold L + C-Right, Left, Up, C-Up, C-Up, Right, Down, Up), you should have 31 tapes now. Officer Dick will not be unlocked at this time because you used the code. Next just play in career mode and type in the Private Carrera code (Hold L + C-Left, C-Down, C-Right, C-Down, Up, Right, Left) and now you got private carrera with out Officer Dick.