I've just ordered His Family by Ernest Poole (the first winner--1918) from the library. I've read in relatively recent years quite a few Pulitzer winners;
The Age of Innocence, So Big, The Good Earth and Gone with the Wind and that just gets me up to 1940.
I think my goal for reading in 2009 will be to try to read all of the Pulitzers that ended in the year 9:
The Magnificent Ambersons will be next (1919) followed by
Scarlet Sister Mary, 1929. I realize that some of these books may be impossible to find.
This looks like a great challenge!