Anyone here have experience with making PCB's?

looking to use this service: http://imall.iteadstudio.com/open-pcb/pcb-prototyping/im120418002.html

got all they way to generating the gerbers (using the file on the download tab on that site)

but i seem to be missing this file: Outline layer: pcbname.GKO

anyone know how i generate it?