A digital museum exhibit put together by the Library of Congress, including photographs and manuscripts.
The foundation website on Whitman includes a wide selection of poems and, better yet, podcasts about Whitman during the Civil War, as well as a segment called "Was Whitman Really Gay." Also, a number of interesting articles can be found here.
An online exhibit on Whitman from the National Portrait Gallery.
The best website on Whitman that we he have found so far: you can find e-texts of all of the separate editions of Leaves of Grass here, as well as letters and criticism. Make this your first stop.
A photograph of Whitman (the guy with the beard) and his friend Peter Doyle from 1865, the year this poem was written. Nice hats, boys.
The title page of the 1867 edition of Leaves of Grass, in which "When I Heard the Learn'd Astronomer" first appeared.
This book is called a "cultural biography" because it attempts to give a history of Whitman through the culture to which he belonged. That culture was defined by political oratory, a vibrant theatrical culture, and an emerging popular interest in science, among other things.
Bet you'd never thought you'd see an illustrated children's book here, did you? That poor kid on the cover looks so unhappy. Is that a rocket in his pocket? Yes, yes it is.