Manuel Canales S.C.
- Customhouse brokers. Contact information, office location, and shipment tracking.
- http://www.mcanales.com/

Tour By Mexico - Coahuila: Piedras Negras
- A brief informational page.
- http://www.tourbymexico.com/coahuila/pidrnegr/piedrasn.htm

Elysa
- Distributor of floor tile, marble, saltillo tile, ceramic tile, and stone. In Spanish and in English, site includes information about the company and its products, including photos and contact information.
- http://www.elysa.com/

Piedras Negras Industrial Park
- Includes information about the facility, contact information, and a map of the location.
- http://www.parque-ind-pn.com/