John Tartar wrote:
Does anyone know of a simple, but free PCB layout software.

Or a way to convert .pcb files from EXPRESSPCB to industry standard format.

It might be worthwhile to look at the various ports in the FreeBSD
CAD library. Chipmunk and electric are among them, though neither seems
to emphasise PCB layout. Perhaps there are other, more appropriate offerings.
http://www.freebsd.org/ports/cad.html is a reasonable place to start

Good luck,

bob prohaska