This site is being developed by a group of variant collectors updating the work of Ralph Nozaki and Dick Gilkeson. It is in progress and Mike Cady who is pointing it has been very helpful with questions and is interested in input from other variant collectors on additions to the effort.
They have a working definition of a variation they will list, but for most issues they mention in notes to the lists many well known variants that are more in the nature of recurring print defects.
The site will eventually include basketball and football as well
http://baseballcardvariationsguidebo...wordpress.com/