I found this website while looking for a solution for my Zen Store.

This guy has a drop down menu where a user can select a car, and then it triggers a list of its models and then the year of the car.

I would like to get something like this for my store.

Any advice?
Is it a contribution or outsourced work?
http://radiatorwholesalers.net/index.php

View the link to get an idea of what I was talking about.