Carlo,
I don't think you'll find the exact photo.net sourcecode anywhere,
as it is a fairly customized ACS 3.4, if I remember correctly.
OpenACS 4.5 has similar features so probably offers the right
base for what you're trying to do. The photo gallery is not quite as
powerful as the highly customized photo.net version, but
certainly exists, and ecommerce capability is on its way thanks
to some work from Furfly helping us out with dotLRN events
(specifically paying events).
