Okay, so there’s not an OFFICIAL Hello Kitty iPod (yet), but with a little firmware hacking and some icon replacements, you can turn your existing Pod into a KittyPod, or any other “re-branding” you desire.
Engagdget has a trusty HOW-TO. Ironically, the resorce-hacking app, iPod Wizard, only runs on a Windows machine. Following the instructions given in the how-to, the upgrading looks pretty straight-forward. This hack allegedly works with the Minis as well. Of course the icon-hacks look best on the color iPod Photo, as seen here.