Linework, more than color matching, helps make a 
cel look "real". People are going to notice that 
there's something "not quite right" with the eyes 
before they realize your canary yellow and their 
canary yellow are two steps apart. ^_^ Some 
people get around this problem by tracing a 
source image. Other people get around this 
problem by making fifty rough drafts before 
they're happy with a final drawing. Whether a 
fancel artist is supposed to be at the level of 
the animator or a regular fanartist, and produce 
wholly original work; or if the fancel artist is 
at the level of merely a cel painter, where they 
ink and color in other people's art, varies and 
is a different conversation completely. ^_^

The only settei that I've seen that have had 
color references on them have been for CG shows-- 
I think I saw some somewhere for Saiyuki. Perhaps 
others have seen them for cel-animated shows, but 
I've only seen color-model cels for cel-animated 
shows, which are different. Their usefulness in 
general, however, is going to be limited, as 
studios use pre-mixed paint that you can't 
necessarily buy straight off the shelves. 
Likewise, line art really hasn't been hand-inked 
in ages, so I don't think people really sell pens 
specifically for animation art.

You can find animation art supply stores online 
pretty easily. Chromacolour, for example, sells 
animation/cel art kits. I've never used them, but 
they might be worth a try if you want to go that 
route, rather than craft acrylics and off-the-
shelf acetate.

In general, though, there are as many different 
ways to make fan cels as there are fan cel 
artists, and their techniques tend to concentrate 
on having a pretty finished product, rather than 
using a method and materials that are identical 
to a studio's process. ^_^ Good luck!