Hi,
i am building mine as some people know. This what i have got so far. Structure of categories and links.
http://www.netgids.com/cat-10.php > this is the deepest for the moment
I also have finished the admin for adding, deleting and editing categories and links. Still have to make the forms.
My server in belgium was out for a few weeks so i havent got much yet.
The paypal module is on its way.
Let me know what you think of the design :p
BTW site is in dutch if you were wondering. If its finished im gonna make an english one to.