Rhodia Polyamide
World wide producer of polyamides . Manufactures polyamid 66, basis polymers and fiber and yarn. Graphically intensive site but contains lots of information on polyamides.
http://www.rhodia-polyamide.com/

Ems Chemie AG
Production of customized engineering grade plastic nylon homopolymers and copolymers based on polyamides and polyesters.
http://www.emsgriltech.com/

Thermech Corp
Manufactures Teflon coatings, powder and specialty plastics, ECTFE, PVDF, polyamides, compression modular moldings. Also, precise tolerance machining.
http://www.thermech.com/