I sent a test email via your form page, and it seemed to send fine. All that needs to happen now is to set the form into one your own template's pages, if you want to. There is a pdf file that shows steps how to do this. If you have problems with that, I have attached a copy of how your finished 'contactus.php' should end up. If you like, you can either use the attached as a reference when making your own changes, or if you want you could just use the attached to replace your existing 'contactus.php' file. (Back-up your own file first in case you want to revert to it).
Don't forget that you still have to change the 'Contact Us' link in your 'contactthanks.html' page so that it links to 'contactus.php' and not 'contact.html'.
[Jason, - the poster was referring to difficulty in adding the CFSP code to his existing contact form, which you asked to see. So, for one, there is no hand coding of any functions going on . What you are seeing is part of an original template that had its own simple email script - along with a recommendation for (and link to) WebAssist's Contact Form Solution Pack. I have the same template. So (for two!) the function to send the email is not in a PHP code block because it was an html form in an html page with the action posting to contactengine.php. The issue was about advice on how to integrate the WA script(s) into an existing HTML template's pages and menu structure.]