We are still searching for game pictures and screenshots for Initial D (PlayStation). We do not have any cheats, codes, or hints yet.

Beat each driver in story mode once to unlock 3 more cars.
Beat each driver twice in story mode to unlock 5 more cars.
Beat each driver three times in story mode to unlock one more car.
Finish first in D-Check mode to unlock the last bonus car.

Beat practice mode under the different difficulty settings to unlock new tracks.