The folks over at Brides.com have put together a nice collection of handmade valentines and valentine treats to make for your loved ones, inclduing my little matchbox valentines. There's even a PDF you can download with the patterned paper, so all you have to do is cut it out and wrap it around your matchbox. (And don't miss the cute cards designed by Sally Shim and Nice Package.)
Note: I've heard from a few concerned folks who don't think you should be putting candy in matchboxes, as they could possibly contain traces of chemicals leftover from the matches. If this concerns you, other options would include lining your box with patterned paper, using wrapped candy, or making little cards to fit inside instead!