Copyright infringement by LynxsDen

Hello,
My registered copyright graphics were grabbed and included in these two skins:
http://www.skinbase.org/rate.php?skins=23692 AND
http://www.skinbase.org/rate.php?skins=23691
The author never asked for permission to use my work, and I would like the skins deleted please.
My originals are on file at the U.S. Copyright Office, and also appear on my website samsilverhawk.com If you visit, please bear in mind that my site is password protected, so one must enter at http://samsilverhawk.com/rules.html and follow the simple instructions given there.
Thanks,
Sam