The contact form can be used in Expresion Web as well as in dreamweaver.
To use your expression web template, you will need to create a new php page based on the template, then copy the contact form code into the template.
There are three blocks of code on the original contactus.php page:
1) The code in the head, from line 1 to the doctype tag.
2) The Form, from the opening form tag to the closing "</form>" tag
3) The spry script. This is the <script> to </script> tag code just before the closing </body> tag.
copy theses three code blocks to the new PHP page you create from your template.