I went to a public school in the 90s and our education of the American frontier and expansion west was brief and biased. It can basically be summed up as "The native Americans were happy peaceful environmentalists, then white European settlers showed up and killed them all. Now let's move on to World War 2".
Obviously the real history is far more complex and nuanced. Many different tribes, each with their own customs and culture were introduced to Europeans in varying groups from lone frontiersmen, to family settlers, to government actors and militias. I'm sure there were places and periods of peace and places and periods of turmoil, I'm sure there's blood on the hands of many people, and I'm sure most people involved were just trying to survive having been born into difficult circumstances.
Are there any good books for the layman that give a realistic overview of the period rather than either whitewashing history as "settlers arrived to empty land" or presenting it as 'good' natives versus 'bad' european settlers?
The simplistic, non-PC version of history is that European-descended settlers and administrators tried to eliminate native peoples and their cultures. Robert Hines is a fairly standard author to recommend for American West history, although amazon lists The tremendously bad Sun Chief as one of his, which it is not. Avoid that one. Otherwise, it's hard to recommend 'unbiased' histories of anything because they simply don't exist.
Have you seen the U.S. Colonial section of our book list? That list would be a great place to start browsing. I'll also make some recommendations here, too, starting with more entry level texts and moving to more complex...
1491: New Revelations of the Americas Before Columbus is the best entry level book. There are some issues, Mann is a journalist, not a historian, but the book is engaging, accessible, and a wonderful place to start your journey.
Facing East From Indian Country: A Native History of Early America is probably the next easiest. Richter places you in the story of the Americas from the Native American perspective. I found the book to be an engaging introduction and a helpful mindshift to start thinking about the history of the Americas from an indigenous point of view.
Seven Myths of the Spanish Conquest is the next easiest. Restall packed this relatively brief book with so much awesome that I recommend it to anyone wanting to dive into the complexities after contact. It is a little denser than 1491, but don't let that scare you. This book will rock your world.
Before the Revolution: Americas Ancient Pasts and One Vast Winter Count: The Native American West Before Lewis and Clark Will be roughly the same difficulty/density. Both authors are wonderful historians, and the books are chocked full of great information, but the writing is denser than my previous suggestions. Don't let that stop you, but just be mindful they aren't as much beach reading as the others.
Hope that helps! Let me know if you have a specific place and time of interest and I can make further suggestions. Good luck on this new reading adventure!
A couple thoughts are The Ecological Indian: Myth and Reality by Shepard Krech III, and then its refutation anthology "Native Americans and the Environment, Perspectives on the Ecological Indian".
That's just for talking about the environmentalism of the Noble Savage. But I second "facing east in Indian Country for an overview.
Check out Kent Lightfoot's Indians, Missionaries, and Merchants. It is confined to looking at California, but it is one microcosm of the frontier. An important aspect of the book is how anthropologists chose to study certain tribes.