United States Abraham Lincoln Bicentennial Commission 

Lincoln Resources Online:
Abraham Lincoln Presidential Library
The White House Biography of Abraham Lincoln
Abraham Lincoln Historical Digitization Project - Illinois years (1830-1861) 
Abraham Lincoln Art Gallery - Contains digital versions of Lincoln photographs
Abraham Lincoln Resources - Speeches, Books
Abraham Lincoln Institute - Latest in Lincoln Scholarship
Abraham Lincoln in Ohio - Abraham Lincoln at the Ohio Statehouse
Abraham Lincoln Memorial - Washington, DC 
Abraham Lincoln and the Politics of the Civil War - From Explore Pennsylvania History
The Lincoln Institute - Supports the study and research of Abraham Lincoln.
The Gettysburg Address at Cornell University - Provides an in-depth examination of the Gettysburg Address, and an online look at Cornell University's handwritten copy by Abraham Lincoln.
The Library of Congress - Mr. Lincoln's Virtual Library
The Lincoln Collection - Housed at the University of Delaware. Available access to pictures, signatures, and documents housed in the collection.
Lincoln Heritage Trail - Interactive Map, Kentucky
The Lincoln Museum of Kentucky - Kentucky's official Lincoln Museum. The museum presents various scenes from Lincoln's life.
Lincoln North - Mcgill University, Canada. The Joseph Nathanson Collection of Lincolniana. Virtual research collections concerning Abraham Lincoln and his life.
Mr. Lincoln's White House - A look at the Lincoln White House
Lincoln's Archives - The Lincoln Archives Digital Project provides access to primary and secondary sources written by Lincoln or concerning Lincoln and his administration, from the National Archives and from the Library of Congress. This site is endorsed by the National Lincoln Bicentennial Commission.
Mr. Lincoln and Friends - Lincoln's Friends and Peers
The National Archives - contains original letters, telegraphs, speeches, and correspondence
C-SPAN: Lincoln 200 Years - C-SPAN site devoted to Lincoln themed programming and resources.
Lincoln and The Quakers - A look at the correspondence between President Lincoln and the Quakers. Research done by Swarthmore College.
21st Century Abe - An online resource of links in celebration of Abe's 200th birthday.
Uncovering the Real Abe Lincoln - Time Magazine's examination of Abraham Lincoln's life and presidency.
Abraham Lincoln Association - The Association's site has education resources, and information on upcoming awards and events.
Lincoln's Washington - Experience Washington, DC as Lincoln saw it when he was a Congressman and President. Site is from the National Trust for Historic Preservation.
Beyond the Log Cabin - Kentucky HIstorical Society's page on the life of Lincoln.
Lincoln at the Smithsonian - The Smithsonian's exhibit on Lincoln.
Lincoln Studies Center - Housed at Knox College. The Lincoln Studies Center is is dedicated to the study of the life and work of Abraham Lincoln.

Abraham Lincoln Locations 
Abraham Lincoln's Birthplace - Hodgenville, Kentucky
Abraham Lincoln's Boyhood Home - Indiana
The Birthplace of Abraham Lincoln - National Park Service
Ford's Theater, Washington, DC - The location of Lincoln's assassination by John Wilkes Booth
Lincoln Home - Lincoln's home in Illinois before he became President
Mary Todd Lincoln Homesite - Abraham and Mary stayed here after their marriage

Abraham Lincoln Bicentennial Commissions, by state:

Washington, DC
North Dakota
Rhode Island

Tri-State Lincoln Bicentennial - Combined Site of Kentucky, Indiana, Illinois