A great site by the University of Virginia.
A brief biography from the Academy of American Poets.
Modern American Poetry site on Frost with lots of great commentary on his poetry.
A short article on Robert Frost' early days and critical reception.
This photo was taken at some point between 1910 and 1920.
Here is an image of an older Frost.
A 2000 biography by Jay Parini.
Library of America editions are the best.