feathersite.com has probably the world's best collection of photos of different breeds and varieties. However, it can be daunting as there are so MANY breeds, and clicking through the links to see them all could take days. Henderson's breed chart is a good place to start by sorting through the traits that he prefers, and will narrow the breeds down a bit. A good hatchery catalogue will have photos and descriptions you can also use to begin sorting out the breeds that are of interest, as well as the ones that he does not care for. Once he has several breeds in mind, then check out feathersite and the breed clubs for those breeds (usually available as a link from feathersite).
Once he has a better idea of the specifics he is looking for, come back here for recommendations for breeders of those breeds, or look in the Poultry Press ads.