The first blurry image of Heath Ledger in an early incarnation of his The Joker gear leaked a couple days ago. It's kind of hard to make out what he looks like, but it's a start.

http://www.superherohype.com/news/topnews.php?id=5530

Supposedly, some pages from the script have leaked online. I haven't read them, nor do I know if they are real:

http://www.filmick.co.uk/2007/04/side-after-side-of-rorys-first-kiss.html