If you are looking for some Halloween clip art for your crafting needs, check out the About.com Clip Art site for images like the witch on a broom with moon pictured. You can use clip art for all kinds of crafting, but you can also use it for mixed-media jewelry making as well.
Resin, of course, is the first technique that comes to my mind when I look at something like this. You could use the basic instructions from my Halloween Resin Cabochons project. The stickers I used were not made of paper, but if you were to print up clip art like this on an ink jet printer, then you’d first want to seal the edges of the paper with something like Modge Podge to prevent the ink from bleeding when you put it in the resin. For a mold, consider using an old (not to be used again) ice cube tray.