You could use the EXISTING "product URL" feature in zencart.
When you add (or edit) a product, in the product data input screen there is a field into which you can insert a URL for a product's "webpage".
If you create a range of EZpages, for example, you can prevent them from taking a menu link by not activating these in the EZPages header/sidebox/footer options, but giving them a sort order of, say, "1". This activates the EZPage, but its link won't display anywhere on your site's menu schemes.
Then, in your product add/edit screen, insert the FULL PATH to that EZPage... eg:
http://www.YOURWEBSITE.COM/index.php...page=page&id=2
(note that - as per the instruction - you omit the "http://")
In a default install of ZC, this link will appear to your visitors right at the bottom of the product info page, but re-positioning it is easy...
Just open (for editing):
includes/templates/template_default/templates/tpl_product_info_display.php
(do this on a COPY of the file on your local machine).
You will see that the page elements are neatly delimited by comment tagging <!-- bof xxxxxx --> then some code <!-- eof xxxxxx -->
Find the one encased by:
Code:
<!--bof Product URL -->
some code here
<!--eof Product URL -->
CUT that section and PASTE it above a section element of your choice.
You can also edit some language defines to change the label and message of the resultant link if you want to.
(As the tpl_product_info_display.php is now CUSTOMISED, you should add the edited file to:
includes/templates/YOUR-TEMLATE/templates/