By Hector
Hi Coderbuddy,

The PCB service is relatively new. We have not updated the page with the uploading capability, we are working on it...

In the product overview (description) section there are some notes, and instructions for submitting your design file:

Once you have placed your order, e-mail us your design files along with your order number in the subject. I.E. Subject: Order No.1234: PCB design files
e-mail: Manufacture AT dfrobot DOT com

You can see the details on the store