Working Retriever Central
For retriever enthusiasts with interests in Retriever field trials and hunt tests, breed club working certificates and picnic trials, and hunting upland birds and waterfowl.
http://www.working-retriever.com/

RetrieverTraining.net
A site devoted to training retrievers, and host of the Retriever Training Forum discussion board.
http://www.retrievertraining.net

American Kennel Club
http://www.akc.org