I was able to get the PDF for $5.00 instead of $25 for the book/PDF bundle on O'Reilly website. Click the "Add bundle to cart" button and the delete the print book version from your shopping cart.
From MacNN:
David Pogue has published a PDF version of iPhone: The Missing Manual. Areas of coverage include the phone and organizer, discussing various syncing topics even Apple never dreamed of, like syncing a single iPhone with multiple computers, or using the iPhone as a data bucket to merge the address books from several different PCs. It also tackles non-obvious problems as solving the "two-mailbox problem" and remedying the iPhone's lack of a spam filter, and discusses the iPhone as a computer and a phone. The 304-page book is priced at $20.
From MacNN:
David Pogue has published a PDF version of iPhone: The Missing Manual. Areas of coverage include the phone and organizer, discussing various syncing topics even Apple never dreamed of, like syncing a single iPhone with multiple computers, or using the iPhone as a data bucket to merge the address books from several different PCs. It also tackles non-obvious problems as solving the "two-mailbox problem" and remedying the iPhone's lack of a spam filter, and discusses the iPhone as a computer and a phone. The 304-page book is priced at $20.