You can't!
Check online, partycity.com, buycostumes.com and halloweenexpress.com all sell a variety of different Wizard of Oz costumes, although Merlin is not a character from the Wizard of Oz. But all those websites also sell Merlin and general wizard costumes as well.
Yes. The wizard of Oz is a musical.
Try Target, Walmart, Best Buy.
nowhere
Daniel Scott was the producer of The Wizard of OZ
The Wizard of Oz was a musical play.
"The Wonderful Wizard of Oz" (1910).
Wizard of Oz costumes can be obtained from the following sites: http://www.wizardofozcostumes.com/, http://www.halloweencostumes.com/wizard-of-oz-costumes.html, and http://www.costumecraze.com/Theater-Costumes-Wizard-of-Oz-Costumes.html.
Frank Morgan, AKA the Wizard of Oz.
The Wizard of Oz lived in Emerald City.
Google study questions for The Wizard of Oz.