unix pipe at work

I wanted to copy a large amount of files into my iTunes library.

Bummer, a computer got disconnected right in the middle, after 5 hours of copy...

how do I resume where it stopped ?

I saw that every directory u until letter D was already copied.

After a few tinkering, I finally found how to not repeat the copy already made :

find . -maxdepth 1 |  | grep '^..[C-Z]+*' | xargs -Ifrom cp -Rvf from /bibliotheque/music