James Madison's "Advice to My Country", edited by David Mattern. A wonderful collection of quotes from probably the most brilliant of our founding fathers arranged by subject. Subjects range from the troublesome issue of slavery to personalities such as Thomas Jefferson and John Adams. 

James Madison: A Biography, by Ralph Ketchum. A detailed yet readable review of the life of the "Father of the Constitution." 

James Madison: The Founding Father, Robert Allen Rutland. Available for the first time in paperback, James Madison: The Founding Father is a lively portrait of the man who essentially fathered our constitutional guarantees of civil and religious liberty. Focusing on the role Madison played at the Continental Congress and in each stage of the formation of the American Republic, Robert Allen Rutland also covers Madison's relationship with his beloved wife, Dolley, his fifty-year friendship with Thomas Jefferson, and his years as a respected elder statesman after serving as secretary of state and fourth president of the United States. 

James Madison on Religious Liberty, edited by Robert S. Alley. James Madison was famous for his beliefs in religious liberty which led to the first Amendment of the Constitution. 

If Men Were Angels: James Madison and the Heartless Empire of Reason (American Political Thought), by Richard K. Mathews. 

The Sacred Fire of Liberty: James Madison and the Founding of the Federal Republic, by Lance Banning. Hardcover or Paperback 

Jefferson and Madison : Three Conversations from the Founding (The Merrill Jensen Lectures in Constitutional Studies), by Lance Banning.  
Hardcover or Paperback 

The Presidency of James Madison, by Robert A. Rutland. From the American Presidency Series. 

The Last of the Fathers: James Madison and the Republican Legacy, by Drew R. McCoy. A study of Madison's later years. 

James Madison and the Search for Nationhood, by Robert A. Rutland. A wonderful catalog of Madison related items from an exhibit that opened the James Madison Building at the Library of Congress. 

The Great Little Madison, a biography of James Madison for younger readers by noted children's author, Jean Fritz. Now in Paperback

James Madison: Fourth President of the United States, by Susan Clinton. The Encyclopedia of Presidents biography for younger readers. 

Writings of James Madison: 

The Debates in the Federal Convention of 1787 

The Federalist Or, the New Constitution, with Alexander Hamilton and John Jay. 

The Federalist Papers, with Alexander Hamilton and John Jay. 

The Republic of Letters: The Correspondence Between Thomas Jefferson and James Madison, 1776-1826, edited by James Morton Smith. 3 volumes. 

The Mind of the Founder: Sources on the Political Thought of James Madison, edited by Marvin Myers.