Jim, it seems to me that the relationship between technology and centralization depends on the cost of the technology, the thing that determines who has access to it. When a new technology is introduced, often it’s so expensive that only the upper class and State has access to it, so that helps centralize power. But then as the cost of the technology falls and more can acquire it, the process can be mitigated or even reversed.
Jared Diamond is a big name in this area among popular historians. I’m not a big fan of his work because he takes a hard materialist interpretation of everything (i.e. ideas don’t really matter), but he writes well.