Via Boing Boing, some scans of the original Denslow illustrations from The Wonderful Wizard of Oz are online at “BibliOdyssey: An Original Oz“.
Of course, there’s also the Library of Congress Rare Book and Special Collections Division’s online The Wonderful Wizard of Oz.
And, there’s news from the Sci Fi Channel about their re-imaging of Oz in the Tin Man miniseries, including a teaser trailer and an announcement that Richard Dreyfuss will play the equivalent of the wizard.