Introduction to PHP Programming
Basic description of the language, how to setup a simple script, how to build forms and how to use common functions.

SourceGuardian
Excellent tool to protect your PHP source code. This program will encrypt your code so that noone else can read and steal the source.

Zend PHP Development Software
Here you will find an intelligent programming environment to code your PHP scripts, tools to protect your source code and more.

Programming PHP
Helps you up the PHP learning curve, very nearly guaranteeing that you'll find in its pages an example that illustrates every fundamental aspect of the language and its most important extension modules. Plus, there's some cool advanced stuff, like recipes for manipulating images, working with Extensible Markup Language (XML) content, and generating Adobe Acrobat (PDF) files.

PHP and MySQL Web Development
Introduces readers (who are assumed to have little or no experience with the title subjects) to PHP and MySQL for the purpose of creating dynamic Internet sites. Authors Luke Welling and Laura Thomson's technique aims to get readers going on their own projects as soon as possible.

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 (those that rely on database queries) and full-on Web applications, such as those that require session management and maintenance of user rosters. Tutorials in both subjects begin with the basics and proceed through moderately complicated stuff, though there's no absolutely comprehensive reference here.

Building ASP Pages
Intended to teach the fundamentals of using a scripting language to create an .asp file. You will learn how to accomplish a wide range of basic programming tasks, from creating a loop to manipulating a database and processing transactions.

Developing Web Applications
This guide provides an overview of Web application design and introduces the more advanced topics of building components and ISAPI extensions, data access, Web-based transactions, and performance.