Pocket is a website that sells and auctions cel 
from various anime and in my opinion has some 
great cels if you catch the updates right.   
They ask that people don't post a link to their 
site though so I can't pass it along.  Not sure 
why they have that rule unless they're afraid 
they can't keep up with a higher demand.  I 
found them by surfing the web for CCS cels when 
they're site came up.  Hope this helps though I 
know it's vague.  ^_^