are you referring to adding a captcha in your web forms? i checked a couple of websites for manually adding captcha on web forms and i ended up with this website Boutell basically its like a tutorial on how you can add captcha to your web forms and use it to your own php pages. it explains everything that you need to do from start to finish. how to add, implement and make it work for the letters to the sounds. hope this website will be useful for you.