Kit,
I just go to the authentic stores such as the mexican stores (I'm half mexican but don't speak any spanish! Fun shopping there
) They usually sell chicken necks there and tripe. I was even shocked that
Whole Foods (that link has the stores in your area) started selling chicken backs (HUGE portions), livers, gizzards, turkey and chicken necks, and all that other yummy stuff for very cheap prices. All their meat is organic so even better. The butcher told me that people ask for scraps all the time for their dogs and they decided to keep that in a section now. They packaged together 3 large chicken backs and sold it for $3.00, I thought that was pretty good for being organic.
-Jenette