Hi Randy, there is a way to find out cards that are in your collection or trade listing that are missing images. When you go to your collection, there are a bunch of reports below the Collection/Want List/Trade List. They all look like a bunch of blue ovals. One of them is "Cards in your collection missing images on the site". This includes both in your collection and trade list.
As scans are added, they will be removed from this listing.
I hope this helps. Thanks, Brian
I am one of the members that helps within the site. I work closely with the IRs and can answer most questions. Please send me a message if there is anything I can assist with. If I don't know, I can certainly try to figure it out or direct you to a resource.