PHP Category Dropdown for Zen Cart ecommerce

[droppy]

I was wondering if anyone could point me in the right direction for creating a dropdown menu for Zen Cart.

I have looked at the ones that are available at zencart but they dont really cut it for what I need.

Example of what I would like, or close to it:

http://www.ethicalsuperstore.com/

I dont mind making a go at it myself but would need some sort of tutorial or gude to get me started. Im new to PHP and not that good yet. lol

Any help or pointers would be greatly appreciated. :)

regards

Droppy