Two spectacular auctions coming up:
Heritage Auctions' Largest Animation Art Sale Ever: https://youtu.be/lV-M5FxNaWo
The Art of Peter and Harrison Ellenshaw: https://youtu.be/l5CopS3WeAM
The Baum Bugle is normally only available to members of the International Wizard of Oz Club (to find out more, follow this link).
Fortunately, the International Wizard of Oz Club has a very, very limited number of copies (no more than 25 I believe) that they have agreed to sell to readers of the Disney History blog and to members of the Disney History Institute Facebook page.
The cost is $15 apiece, including postage to US addresses, and interested buyers need to make a PayPal transfer directly to email@example.com.
Full disclosure: I contributed in one way or another to all of them.