What is the word for a human 'copier'?

I think you're looking for the term "scribe". See http://dictionary.reference.com/browse/scribe

scribe

• a person who serves as a professional copyist, especially one who made copies of manuscripts before the invention of printing.
• a public clerk or writer, usually one having official status.
• Also called sopher, sofer. Judaism. one of the group of Palestinian scholars and teachers of Jewish law and tradition, active from the 5th century b.c. to the 1st century a.d., who transcribed, edited, and interpreted the Bible.
• a writer or author, especially a journalist.

amanuensis

amanuensis [əˌmænjʊˈɛnsɪs] n pl -ses [-siːz]

a person employed to take dictation or to copy manuscripts

AHD