Hi

As far as I know, there aren't any anime cel 
shops in NYC.  There are some good places to 
buy other anime goodies tho...Check out the two 
big Bookstores, Asahiya (Near Grand Central off 
Vanderbilt)and Kinokuniya (near Rockafeller 
Center) for manga, cds, dictionaries, books, and 
magazines.  There is also Image Anime (37th and 
6th ?), last time I went they didn't have cels 
for sale... but they have many models, toys, 
CDs, videos, and books. There was a store by 
Union Square (Near NYU) but I'm not sure they 
are there anymore altho I heard a rumor that a 
new store opened there on campus.

If you are looking for American Animation Cels 
there is Animazing in Soho (on Broome St)

You can also visit Chinatown for scrolls, cards, 
SM cds, posters, keychains, Boot DVD's, videos, 
toys, video games, Pocky, etc etc.  

Good Luck! Hope this helps

Ame