Publisher's blurb:
Generally, designing a culture for a book or a game presents you with a choice: either you base it on real-world cultures and likely end up with something that could be described as "Fantasy Bedouin with some Navajo bits tacked on" or you run hog wild and run the risk of overlooking something that, however innocuous, turns out to be vitally important for that type of culture.
There's another way to handle this dilemma, though. By researching each culture of a given type and taking note of their common characteristics, you can create a plausibly-developed culture that doesn't noticeably take its cues from any real-world counterparts. That would take an enormous amount of effort, though, but luckily for you I've gone ahead and spent the time, bought the books, and pored over the scientific journals so that you don't have to!
How-To: Horse Nomads is a summary of the characteristics that were held in common by horse nomads on both the Eurasian Steppe and the American Plains.