Faith Bass Darling's Last Garage Sale question

This question isn't really about the book. It's a question about listing the book. How do you add an "additional edition" when it tells you that it doesn't exist--and you've just downloaded it so you know it does exist? I run into this once in a while when trying to add the kindle edition. I usually just use what's there, but really I'd like others to know it exists, too. Is there a method or someone to contact?