I found some cheap cassette tapes at DI. They aren't as colorful as I want, but some paint could quickly fix that problem. I decided to use cheap lined paper for the pages because that's about all I have and I think it fits with the "retro" theme. This was a quick project because there were already holes in the cassette tapes and it was so small. It only took about 20 minutes to sew together. Here are some pictures:
I've also updated my "examples" page on PaigeBooks to show this newest project.