I need to create a web form for my site, but I do not know php. Can you please recommend me a php script or some free form builder?

So far I found freedback and this free <a href="http://www.emailmeform.com">html form</a> builder which unlike freedback does not show any advertising in the free plan! ;-)

We have a PHP script resource section on the forums that you could take a look through. There should be a couple of scripts there for you