Before David Reich’s book, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past, I highly recommend a new preprint from Pontus Skoglund and Iain Mathieson*, Ancient genomics: a new view into human prehistory and evolution.
It’s basically at the sweet spot for a lot of readers: doesn’t overemphasize methods or archaeological minutiae that’s hard to follow. That being said I do think you would benefit if you read two things which would complement in those directions, First Farmers: The Origins of Agricultural Societies, and Ancient Admixture in Human History.
* I have to say, I consider Iain a friend, but am I the only one a bit perplexed by how a British person can have such a difficult to spell version of his name? I always have to look it up!