C. Ped. stands for Certified Pedorthist.
The field of Pedorthics is the study of footwear and supplemental devices for footwear; including orthoses, prostheses, shoe modifications, shoe fitting and shoe fabrication.
The licensing board for Pedorthics is the BCP (Board for Certification in Pedorthics) The BCP is recognized by the American Academy of Orthopedic Surgeons and the ABC (American Board of Certification in Orthotics and Prosthetics).
For more information on Pedorthics, please go to the BCP website or the PFA (Prescription Footwear Association). Both sites are good resources for reliable information.