Generally I recommend any book by O'reilly for anything tech related. There is a couple books I've been drooling over, but I learned PHP without a book (whereas I bought a book on Java and haven't touched it yet, and I bought it before I started messing with PHP).

There are so many good tutorial and community sites focused around PHP that anyone with even a touch of C, or any C-like language could easily pick up enough info from.
A good place to start would be the tutorials section on http://www.zend.com

I'm excited for PHP5 too, and not because of the SQLite support, but more for the more advanced OOP. Which is a lot like Java, so much so that many PHP-junkies are saying that PHP is turning into Java... (which is silly I think...).

other places to look:
http://www.phpfreaks.com
http://dotgeek.org
http://codewalkers.com
http://google.com with a search for "php tutorials"

I don't know why, but PHP with it's loose typing and its C-like syntax made it very intuitive for me. I would recommend going over some tutorials and writing a few scripts to get confident with the language and then getting a more advanced PHP book, because I've found that there is a shear abundance of beginning tutorials and a lacking in the more advanced stuff.

Unlike ASP.NET where I've found more moderate to advanced stuff when I am really looking for an introduction to C#, other than a hello world application... (I'm in the process of diversifying my skill-set, gotta get back into the compiled languages too, C++ is in my near future).

Peace,
Dhej