[Skunkworks] Selecting parent and child from db in php

Hi Techies, I have an issue but I know its not big for techies there php gurus out there, am doing a site to search for stuff like if the upper select is vehicle/car make the next one should be model The problem is this; somebody selects a toyota as a car make then the car model should be the line of toyota i.e corolla, premio etc and not subaru's model imprezza... etc anybody with an idea please I will be grateful Rgds Calvin