We also strongly recommend toi send in pictures of girls (heck, even boys) in headbands, especially our Gossip Girl cast. We've got a bunch of graphics here, but toi can also make your own (we'll make an entry where toi can share them).
The mailing address is:
The CW Network
c/o Gossip Girl
3300 West olive Avenue
Burbank, CA 91505
Now aside from old school letter sending we'll be doing email and other forms of communication/promotion. So get ready for that too. If toi can't send in printed headband photos, then toi can certainly do it online.
Don't forget to keep promoting The Headband Project!