I start out with one of those old CD cases that you can remove the middle black part that holds the CD. For my Bellas, I use the pink insert and tape it to the cover (underneath).
Then I stick the stamp to the inside of the case -making sure you don't put too close to the left edge because it will close on the stamp and ruin it.
Today I was shopping at Staples and found on their clearance table, a set of 3 little crates with 12 cd cases and 2 clear drawers for $3.50! I got 3!!! What a deal!! I can't wait to set them up. I will post pics later - once I get my space organized.
I hope you found this idea helpful on how to store your stamps.