The codes should work with the region specified but may work for other regions as well.
Device Compatibility: Action Replay, CodeBreaker & GameShark
Extra Character Kimber
800690B0 010F
Extra Character Eddie
800690B0 010D
Extra Character Irving
800690B0 0110
Mega Points
8009AEE4 FFFF
Extra Character Joshua
800690B0 0112
Extra Character Burg
800690B0 0114
Stop Timer For First Place
8009C7DC 0000
Open All Courses
8006903C 0005
No Time Penalties For Missed Gates
8009AFFA 0000
Extra Character Mars
800690B0 010E
Extra Character Cool
800690B0 0113
Extra Character Bob
800690B0 0111