I was listening to lots of old cassettes I retrieved from the loft and found tapes of  “Black Elk Speaks”.  There are numerous mentions of Tipis in the audio and the reverance the Sioux felt for the tipi is clear.

Here is some info from Wikipedia on Black Elk.

Black Elk (Hehaka Sapa) was a famous Holy Man of the Oglala Lakota (Sioux). Black Elk participated, at about the age of twelve, in the Battle of Little Big Horn of 1876, and was injured in the Wounded Knee Massacre in 1890. In 1887, Black Elk traveled to England with Buffalo Bill’s Wild West Show.