Obviously meat could be eaten, bones used as tools, brains used in tanning, etc... Were there alternate uses for these parts as well? What about other less obvious parts like hooves and offal?
Bones with marrow (besides being used for soup) could be used to paint hides. The marrow was spongy and sucked up pigment much like a magic marker. Bladders were used to store all sorts of things: from water to sharp porcupine quills. Intestines could be used for food casing (much like sausages). Horns could be used for spoons. Eyes and many other parts could be eaten—some of the funkier parts might become dog food. Fat was a food preservative, and rendered fat (tallow) was an essential ingredient for pemmican. Jawbones and scapulas can make useful daily tools, from hide scrapers to hoes. Skulls are used as ceremonial altars. And to the point, buffalo penises are sometimes used in dance staffs.
I don't really know the full answer to your question, but I visited the American Museum of Natural History here in NYC recently. There are buffalo horn headdresses there, which I had never heard of before.
This one is a replication of a buffalo horn headdress that's in the Denver Art Museum.
