There were at least five or six different versions of jewelry displays similar to this. Almost all of them used a regular picture frame. There were different materials used to hold the earrings (even chicken wire!), some had hooks for necklaces, some did not.
I used a regular picture frame, glass and backing removed. I used window screen material to hold the earrings. The only thing I had to buy were the small cup hooks that I inserted along the bottom to hold necklaces ($2.00).
I think it turned out great! Very happy with it!
P.S. That's is NOT a dog collar necklace, it's a bracelet that you wrap around the wrist twice before buckling.
See my inspiration for the project here.