This addon creates tags for a "buy" page linked to PayPal.
Version History: V1.1: included language variables and improved instructions; V1: first release.
Installation: 1) put this file in your addon folder; 2) create a separate template called "buy_template", on which you place your purchase details and your paypal buttons; 3) place the tags as desired.
Tags: <BUY_THIS_IMAGE> - Returns a link TO the buy template FROM the image template. Place this tag on your image template; <BUY_THUMBNAIL> - Returns the thumbnail of the image specified in the URL; <BUY_IMAGE_TITLE> - Returns the title of the image specified in the URL; <BUY_IMAGE_ID> - Returns the image ID of image specified to pass to PayPal buttons; <BUY_IMAGE_LINK> - Returns the first part of a link back TO the image template FROM the buy template. You have to close the tag with </a>.
You can see it (almost) in action at http://www.sophiepasquet.com by clicking "Purchase" on any image page. I say "almost" because the version running there has a considerably more complicated hack that involves creating new dbase fields and editing the admin files. I am prepared to share those hacks but cannot support much the dbase fields.