Recently discovered in the Pulp Magazine Archive are two issues of The Shadow Magazine.
The Five Chameleons
The Black Hush
Amazing. I have plenty of Sanctum's Shadow reprints, but they only reprint the Shadow novels, not the short fiction that came with.
I've also updated the article "A Quick Guide to Finding the Shadow" with this information.
Finally, I am going to bite the bullet, and type up "A Million Words a Year For Ten Straight Years," by Walter Gibson. Expect to see the full text soon.