I don't have the book with me right now so I can't reference any page numbers for you, but currently the earliest verifiable records we have of ancient China begin with the Shang dynasty.These records include the famous oracle bone inscriptions that I'm sure you've heard about.

The myth of Yu comes from the records of the mythical emperors Yao, Shun, and Yu. If you read the original accounts of these myths they're characterized by all sorts of fantastical and mythological references. Our earliest archaeological records begin with the Shang unification of several tribes in 1554 BC/CE. Many current scholars, however, regard the Shang as more of a proto-state than a state because they didn't really expand territory-wise, as far as we can tell, especially in comparison with their successor dynasty, the Zhou.

all of this comes from Patricia Ebrey and Anne Walthall's "East Asia: A Cultural, Social, and Political History." There are other more interesting academic texts about this stuff, but that's a good starting point for a broad overview.