Text of the U. S. Constitution
http://www.archives.gov/exhibits/charters/constitution_transcript.html
The Bill of Rights
http://www.archives.gov/exhibits/charters/bill_of_rights.html
U. S. Constitutional Amendments 11 - 27
http://www.archives.gov/exhibits/charters/constitution_amendments_11-27.html
Historical Federal Receipt and Outlay Summary
U. S. Government Spending (2010)