If you are reading this, then you are interested in learning more about milk's rich history in America. Indeed, there is much to be discovered scattered across libraries, archives, and other sundry repositories.
A good place to begin might be Anne Mendelson's new book, Milk: The Surprising Story of Milk Through the Ages, (New York: Random House, 2008). That should get you started.
From there, and depending on your particular interests, you could inquire further into labor union history, agricultural history, food history, etc., etc. The avenues are innumerable. As far as this project is concerned, I conducted nearly all research within the archives of the Consumers Union and the private collections of the Parodneck Foundation. Places such as these are often the most rewarding sources of historical information.
For a more tactile appreciation of this online exhibit, please visit The City Reliquary Museum and Civic Organization in Brooklyn, NY, between January 30 and May 3. Photographs, ephemera, artifacts, and dioramas will be on view for your pleasure.