The bottlecaps and the Glaze Drops came from Sun & Moon Craft Kits. Apparently their store is closed over Thanksgiving break, but you'll have to check them out when they return! They have some great deals! I was able to make these for under $1.00 each. Maybe even less than that!
Anyways, the way I did it was I printed my images, cut them into 1" circles and then used fabri-tac (any tacky glue would work) to attach them to the bottle cap. Then I placed one of the "Glaze Drops" over the top to give it a bubbled up effect. So easy!