You can drag and drop artwork straight into the cover well or go to the site via the info view (ctrl-click inside the info view and choose 'Go to site', type in the URL of the site and then ctrl-click on the image you want as cover image and choose 'make cover of selected entry'.)
Yes i know that, but what i ment, and what i think iboy ment is if its possible to change the default download link for coverart to a user specified download link, so whenever you add a new film it automaticly fetches art from the site you have chosen...