How can I attach external links to these images in a WP post?

I'm using a modified twenty ten wordpress theme on a simple ecommerce site, that uses wp-Prettyphoto to add a gallery to each product post. I can't seem to make the photos link to an affiliate link for the main photo, or the thumbnails. I can't imagine it is all that difficult, but I'm not an expert and I'm stumped.

I think the code for the product page (single.php) that needs to be changed is as follows:

<div class="product-gallery">
<?php the_post_thumbnail('medium'); ?>
<?php attachment_toolbox('tinythumbnail'); ?>
</div>

If anyone can point me to how I could add an aff link to each of the photos, I would appreciate it.

An example page in question would be:

http://playstationmovecontrollers.org/playstation-move-controller/

Thanks in advance for any pointers,
Kevin