One more thing to say:
I think many languages could be protected if they were better documentated... It might be a fact that many younger native Americans do not want to learn their own language anymore, but there will always be language freaks like us.
I'm personally very interested in Lakota, Chickasaw and Quechua (in the first two languages because I have already done homework about these two languages, mainly morphological analysis, and in Quechua because I'm rather interested in the people and the region where Quechua is spoken)