There are many sites which offer lists of various web-based applications
which use Perl, CGI, PHP to implement a shopping cart on your web-site.
Additional things you may need to consider is security and method of payment.
There are also sites which will handle all the details for you.
You can get a secure site, and they have pages which allow you to access and enter your data and pictures. Then you send you visitors to the special site to purchase, and they get returned to your site when they are finished.
The third alternative is to buy an existing solution which will be installed and maintained at your site. for a fee.
The home brew is most rewarding if you an do some modifications to perl scripts by your self, and follow some instructions for setting up a SSL server for taking creditcard data over the net.
In actuality you can be equally secure if you understand how to set up security issues and certificates by your self, but some customers may hesitate if their browsing software cannot recognize your certificate as belonging to known and trusted networks.
There are several issues which you need to get clear on , but everything is doable.
http://www.google.com
Search for "shopping cart"
and or "CGI scripts" "PHP"
to name a few.