I'm not sure why I ended up purchasing this book because one of the aspects of the Shadowrun World that didn't interest me were the Native American nations. I think the reason that I did end up buying it was because it was selling at a discount, and that was probably because nobody else was buying this book. In fact I never ended up getting volume 1, though I probably did flick through it when I was in a gaming store. However I never really had the money to inflate my Shadowrun collection with that particular book (not that I would considering doing so now).
The story with the Native Americans in Shadowrun is that after years of oppression and being relegated to unproductive reserves where they ended up drinking themselves stupid (similar to what is happening here with the Australian Aboriginal population) the Native Americans revolted and ended up overthrowing their oppressors when they brought magic back into the world (though one may argue that it had never left, just that the ability to be able to use it had been lost).
I did a similar thing with the Aboriginal nations in Australia, relegating the white population to a narrow strip on the East and South coasts, with Perth becoming a city state. Most of central Australia had been returned to the Aboriginals, though the Japanese had invaded and conquered Northern Australia. However, most of the land that I ended up giving to the Aboriginals turns out to be, well, unproductive desert, which is basically what is happening now. As was the case in the United States, it turns out that this desert is not actually unproductive because there is a lot of mineral wealth underground which, I believe, the mining companies are able to exploit without actually paying all that much money to the traditional land owners.
In the United States, the Indians basically get most of the plains and the west coast, and have divided into a number of nations. The two books describe four nations each, this one looking at the northern four nations, while the first book looks at the southern four. Personally I can't remember much beyond that, though there is a nation called the Souix Nation, but that is basically it.