The most famous zither music from the movies was The Harry Lime Theme. Can't remember what it was about, a crime movie of sorts and a lot of it took place in the sewers under Vienna.

There is a local performer who appears at the Deutscher Club of Clark NJ and elsewhere under the name "Dr. Zither" (Dr. Bill Kolb, PhD.). He is quite talented. Bill L. and Mark may have seen him...
Dr. Zither .