Governing documents generally begin with some sort of reason for their purpose. In the United States Of America The reason for forming a new government is explained by The Declaration of independence.
In the United States of America the foundational governing document is the Constitution. All other laws Federally rest on this one single document. State constitutions also rest on the Constitution, and must not contradict it.
All of the constitutions of the individual States, of the United States Of America rest on the US Federal Constitution, and are the founding documents for each state. Because I live in the state of Oregon I will include the Oregon state constitution here.
In the United States not only does the state have founding documents, so do the counties and towns. As I grew up in Josephine county Oregon I have included their county charter here. Your county also has something like a charter and you can ask your county clerk just what that might be. County charters by an in large cover all aspects of the counties government. As a person elected to either town or county government it is a good idea, I think, to know a bit about the charter of the county that you live in,
Cities also have charters that lay out their areas of influence, boundaries of power that are not as powerful as the State, Federal, or County governments. As you look over the founding documents you will discover that Counties, State, and federal governments can have an adverse effect oh how you are able to govern your town or city. As I currently live in Woodburn Oregon I haver placed a copy of their charter as the final part of this discussion on founding documents.
Down The Sewer Pipe - Politically Speaking 