I've never found stock of a Polaroid frame that I was perfectly happy with, so I decided to scan my own. (This is the back of the Polaroid.)
The .psd is ~7 megabytes, it includes a transparent background, a black background, and a whitebackground. It is about 1000 pixels wide, and the resolution is 300 dpi.
If you decide to use one of my photos in your art, please credit me by name ( *digifox
) and link. And please note/message me so I can see your handiwork!