A&E Television
History.com: American Presidents: Thomas Jefferson
This easy-to-navigate site has Thomas Jefferson's biography, events in his life, an image gallery, several video clips.
PBS
Pbs: 24 Historians Interviewed on Thomas Jefferson
PBS presents a transcript from an interview with Natalie Bober, a author of history books for young adults. She covers Jefferson's early life up to his time at the White House. Links to other interviews are available.