The book that I was the Technical Editor for, Cocoa Touch for iPhone OS 3, is now shipping from Amazon.com and should also be in (hopefully) most Barnes and Nobles.
View it at Amazon.com by clicking here.
This book is great for new iPhone developers as well as experienced ones.
You will need some Objective-C knowledge, but if you have some OOP (Object Oriented Programming) experience you should be ok with picking up an Objective-C book as well for as you work through the book.
If you are in a B&N stroll into the Geek, err, I mean Computer Programming section and look for the book.
Feel free to buy a copy to support my good friend and author of the book, Jiva DeVoe.
If you can’t get yourself to that level of geek, at least pick it up and look at the ‘Credits’ page, right before the Table of Contents and then you can go around to all the geeks in that area and say, “I KNOW THIS GUY!” 
This makes 2 iPhone development books that I have been involved in, each one with more of a role than the last, however I can safely say it will be my last as after being involved with the book writing processes and having the author be a close friend of mine, I don’t really have a desire to write one myself (unless it’s an offer I just can’t refuse).
