At first glance it seems that the way to change the link that displays for "Call for Price" products is to edit the function "zen_get_buy_now_button" around line 1145. I see that that the constant FILENAME_CONTACT_US is coded into the function. So probably I can change the call for price button to link to another file by editing this.

However, before I do that, am I overlooking something somewhere in the admin configuration settings that allows you to control where the customer is taken when he/she clicks "call for price"?

In case anyone is trying to do a similar thing, here's what I'm trying to accomplish: some products are available only on a rental basis. I've changed the call for price text to say "Rental Item" but now I want the customer to open a pdf file (or maybe a new EZ page or some other html page) when he/she clicks on the link instead of the CONTACT US page.