Tacky costume jewellery suddenly becomes cool when you make it yourself.
Step 1: Sources for materials
Small crystals (lead glass) or plastic "rhinestones" with flat backs can be purchased at craft stores. These are 2mm in diameter - I discovered later that I shoud have gotten bigger crystals, or smaller magnets in order for them to cover the magnets completely, but the earrings look all right as is. The magnets are neodymium discs 1/8" diameter by 1/32" thickness (3.2mm by 0.8mm), from kjmagnetics.com - very cheap, $2.00 for 25. Superglue...buy anywhere for under a dollar.
Tools: A pair of tweezers or forceps for picking up the crystals (if you can find plastic ones, these would be better than metal), and a toothpick for repositioning.
Step 2: Attaching decorations to magnets
Don't separate the magnets, as it's easier to hold them in a "bar" than to handle them individually. Place a small drop of superglue on one of the ends. Be sure that it doesn't flow down in between the top magnet and the next.
Pick up one of the crystals with the forceps and place it on the glue. You'll find that if your tweezers are made of metal, they will glom onto the stack of magnets, possibly causing you to drop the crystal, which is why plastic ones would be better. An alternative is to place a crystal facedown on a surface and then dab the glue-covered magnet onto it.
Since superglue sets very quickly (duh!), you have only a few seconds to reposition it by pushing it around with the toothpick. Allow the glue to dry for a few minutes.
Step 3: Earring backs - just another magnet
Earrings stuck onto a pair of metal tweezers are pictured here. The backings are simply another magnet.