Below is a link for a tutorial for making Scrabble Tile & Bottlecap Necklaces... http://thebottlecapco.blogspot.com/.
It has lots of nice pictures to help guide you. I think that I prefer the idea of sealing in the image with a sealer or resin rather than using epoxy dots. I fear that the epoxy dots may not make a tight enough seal for durability.
They have reasonably priced bottlecap supplies.