Having spent weeks combing through old magazines, old newspapers, and everything else I could find netted a TON of stuff. Way more than I could ever fit in one(or even two) books.
The Library of Congress has some cool images that for one reason or another I didn't use.
The first is a vintage photo from 1938 showing a Halloween party at a campground.
The second image is a library poster you might have found at the library in 1940.