Verses with the word writer in the Old Testament (2 verses):

Judges 5:14
Out of Ephraim was there a root of them against Amalek; after thee, Benjamin, among thy people; out of Machir came down governors, and out of Zebulun they that handle the pen of the writer.

Psalms 45:1
My heart is inditing a good matter: I speak of the things which I have made touching the king: my tongue is the pen of a ready writer.