My favorite place to buy the most ethical fiber you can imagine, is Tregelly's Fiber farm
, in western Massachusetts. They are a small farm, with a wide variety of unusual fiber animals, and they are just the warmest and kindest people you'll ever meet, and take excellent care of their animals. They have a small yarn and fiber shop off their house, and the farm is a great place to visit, it's a small-scale Zoo, with birds (including a peacock) and goats, and camels, yaks, chickens, sheep, and more than I can name. Their yarns are all dyed with natural, earth friendly dyes. I believe they offer a catalog and yarn samples of their yarns, to order by mail.