Academy of American Poets
Poets.org: Carl Sandburg
Maintained by the Academy of American Poets, this website offers a good biography of Sandburg, plus links to four of his poems, a bibliography, and links to other Sandburg-related sites. Nice resource.
Other
Lisa Lee's Carl Sandburg Page
This website offers a very detailed time-line biography of Sandburg, along with the text of his poem "Home Thoughts," an explication of that poem, a bibliography, and pictures.