The full Encyclopaedia of Alternative Fashion can be found here.
EDIT: HERE, HAVE A KITTYGOTH BEDROOM.
Country of origin
EVERYWHERE! Well, Hello Kitty is Japanese, but I suspect Kittygoths appeared in America first.
Kittygoth is a bit of a joke term for a goth that wears lots of Hello Kitty items, although it has sometimes been used to refer to goths who wear general cat-themed items. The gothic style adopted can be any kind - there are Hello Kitty cybergoth accessories, very pastel goth style items, J-Goth, electro-goth, etc.
La Carmina is probably the closest thing to a kittygoth. She regularly features Hello Kitty and Hello Kitty X items on her blog, although she does seem to have a preference for the other Sanrio characters My Melody and Badtz Maru.
Further reading and resources
Since this is not a recognised subculture, there's not really anywhere I want to link you to. :3