Have you tried the image search on Google?
A few mins, of varying keywords, and I got this one: his character sketch/design page from the artbook. It's not in color, but you can get that from the many color images on the net.
You could also try the anipike (www.anipike.com
) and search for Cardcaptor Sakura, then find the image galleries. I had a great page once, in french, but it had amazing pictures. Can't find the URL anymore, though, sadly.
Hope that helped.
Slightly oddly colored image (its a cell from the second movie): http://cyberpsychos.netonecom.net/Ce...Yue&Sakura.jpg
My search criteria were "yue ccs".