Mail form

Hello!!
I have made a PHP mail form on my site.. but it's doesn't seems to work..Do you know why? Do you have any advices? :)
thank you!! I'm very new to PHP and I'm a little bit confused..

EDIT:

:)

I have found the PHP script here : http://www.ibdhost.com/contact/

and my form action should be here

Let me know if you need more informations.. thanks again!!