United States Treaties
HeinOnline U.S. Treaties and Agreements Library searches treaty text, hearings, official treaty publications as well as unofficial. More information on the unofficial treaty publications can be found here.
United States Treaties and Other International Agreements contains all treaties and international agreements other than treaties to which the United States has become a party during the calendar year.
Senate Treaty Documents- documents identifying treaties received, treaties approved, and treaties actions
You can search for treaties in Congress.gov - a resource provided by the Library of Congress
Treaties in Force is prepared by the Department of State for the purpose of providing information on treaties and other international agreements to which the United States has become a party and which are carried on the records of the Department of State as being in force as of its stated publication date, January 1, 2007.
United Nations Treaty Collection
Background Information on UN Treaties
Finding Draft Treaty Documents
Example of Google Search