If i have Pagetype named Houses.php and template Houses.ss how can i add the contact form to this pagetype.
Also if i use on Houses the tille as house name how can i add the housename to subject value automaticly.

Need something like this:

Subject: Name of house already set on page load
email: client puts email into emailfield
Message: client writes something here

This tutorials show you just about everything you need to know for that type of form: http://www.ssbits.com/newbies/2010/creating-a-simple-contact-form/

I shows you how to add the contact form to the template and how the handle it by emailing it :-)