Just discovered that this can currently be found on Youtube...
The Dreamer of Oz: The L. Frank Baum Story is a film that stars John Ritter as Baum, the man who wrote The Wonderful Wizard of Oz and eighteen of the other Oz books. Also starring Annette O'Toole as Baum's wife Maud, and Rue McClanahan as his mother-in-law.
The film depicts how L. Frank Baum came to create one of the best loved stories of all time, while undergoing professional and personal failures.
-> Playlist on Youtube