(BOOK) Web Database Applications with PHP & MySQL
How to use the PHP server-side scripting language and the MySQL database engine to underlie dynamic Web sites. Tutorials in both subjects begin with the basics and proceed through moderately complicated stuff. Buy Now from Amazon.com.

Apache Web Server
The most popular web server on the web. The server comes with Mac OS X and most Linux distributions, but you may need to download the source and recompile it to get PHP working with it.
Apache Manual

(BOOK) Apache: The Definitive Guide
This book covers Installation --readers find out, step by step, how to set up a Web site (or several) under Apache, and how to set up Web site security and other preferences properly. Buy Now from Amazon.com

PHP: Hypertext Preprocessor
PHP is a server-side scripting language for creating dynamic web pages. PHP can be used on multiple web servers and platforms, the most common is using PHP with Apache.
PHP Manual

(BOOK) Programming PHP
This book is a comprehensive guide to PHP, a simple yet powerful language for creating dynamic web content. Co-authored by the creator of PHP, Rasmus Lerdorf, so you'll learn not only how to program in PHP, but how to do it well. Buy Now from Amazon.com

MySQL Database Server
MySQL is a very fast, multi-threaded, multi-user and robust SQL database server.
MySQL Manual

(BOOK) Managing and Using MySQL
This book has all you need to take full advantage of this powerful database management system. It takes you through the whole process from installation and configuration to programming interfaces and database administration. Buy Now from Amazon.com

(BOOK) MySQL Cookbook
MySQL Cookbook provides a unique problem-and-solution format that offers practical examples for everyday programming dilemmas. For every problem addressed in the book, there's a worked-out solution or "recipe".
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Introduction to Relational Database Design
A slightly more technical look at relational databases and how they are used. mSQL used as example, also knowledge of SQL would be a plus for reading this one.