To find the URL for the image, try visiting the page through your browser and then right-clicking on the photo. There should be an option to view information about the image, including its URL.
If that doesn't work, it may be because the image is being loaded through Flash or some other client-side program. You can use Fiddler or Wireshark to watch what URL its loading.
If you give us the actual URL of the site with the image, we can help you determine how the image is being loaded.