The Constitution of the United States was written in 1787, ratified in 1788, and has been in operation since 1789. Images of the original document and a transcript of the text are available from the National Archives. The National Archives also provides access to the images and transcripts of the Bill of Rights, the first ten amendments to the Consitution written in 1789.
The text of the Constitution along with all ratified amendments can be located in most statutory compilations:
United States Code
LAW FEDERAL 1st floor KF 62 2006 .A2
United States Code Annotated
LAW REFERENCE 2nd floor KF 62.5 .W45
United States Code Service
LAW FEDERAL 1st floor KF 62.5 .L49
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