How do I turn the PCB design on this PDF into a Gerber file to send to batch pcb?
[CMU800MIDIKitPCB2_20071230.pdf](< base_url >/applications/core/interface/file/attachment.php?id=4410)
Short answer: Not at all.
Long answer: By rebuilding the pcb in eagle/kicad/… and then generating the gerbers. You could just home-etch that thing. It’s big, single-sided, …
Jeez that was quick, any suggestions of freeware that can do the task? Thanks.
eagle/kicad/…
I found a DL link for eagle light, that ok?
hmm. The download is only about 10MB. Why don’t you just try? 
yes do it Eagle is an amazing program (cimo is politically correct ) but you may want to give a try to kicad as well cause it doesn t have the size limitation that Eagle has.
cimo is right. Try both. Use the one you like better. If you (dis-)like them about equally use kicad cause it’s free.
Isnt kicad Linux only, regardless I found the mystery .PCB file, I just need to know what next??. and am willing to take a flame for it.
.
Isnt kicad Linux only
nope you can get an instaler for windows as well and osx support will come soon, atm you need to compile yourself if you have a Mac.
If you are using batchpcb.com, they also have a how-to for generating the proper files to suite their needs. Included are some additional scripts (for generating things like the silscreens) and such. It was pretty easy to do, but took a while to get everything perfect. So be ready for learning patience 