Extra Car:
When playing in arcade mode choose any car.
Then play all tracks in order.
You must make a record and at the last track
you will see the staff names.
Then you'll get a new car named Daytona.

Dinosaur Canyon area:
Turn the car around at the starting line, then drive
up the ramp on the right.

Daytona bonus car:
Finish in first place on all tracks in a normal race
under the normal difficulty setting.

Uma horse:
Finish in first place on all tracks in a normal race
under the hard difficulty setting.

Uma 2 horse:
Finish in first place using Uma on all tracks in a
normal race under the normal difficulty setting.