SQL Injection: How To Prevent Security Flaws In PHP / MySQL
http://www.learnphponline.com/security/sql-injection-prevention-mysql-php
http://www.anil2u.info/2010/04/12/how-to-prevent-php-website-from-sql-injection/
http://smashingwebs.com/2010/09/sql-injection-how-to-avoid-it/