Change add to cart button from a submit button to an image

In the wp admin go to the Add to Cart Plugin and select “Image” rather than “Button”. Then make sure you have uploaded your buy.gif to the main images directory, and that should do it.

By the way, there are image replacements for all the store generated form buttons https://www.ecommercetemplates.com/phphelp/ecommplus/parameters.asp#buttons these would be added to includes.php

That worked well, thank you. Appreciate the buttons link too.