American Kennel Club

National Labrador Retriever Club, Inc. (NLRC)

Labrador Life Line (aid for purebred Labradors in need)

http://www.offa.org/  (Hips and elbows)

http://www.caninehealthinfo.org/

http://www.vmdb.org/cerf.html (eyes)

http://www.vetgen.com/color.html   (ChromaGene coat color inheritance chart)