The Collaborative International Dictionary of English v.0.48:

Psalmographer \Psal*mog"ra*pher\, Psalmographist
\Psal*mog"ra*phist\, n. [L. psalmographus, Gr. ?; ? a psalm + ?
   to write.]
   A writer of psalms, or sacred songs and hymns.
   [1913 Webster]