there are three code blocks on the contact page you will need to copy and past into your existing page.
From line 1 until the doctype tag is all of the server side code needed to perform validation and send the email. Copy this code and paste it above the doctype tag on your page.
Then there is the form.
copy from <form.. to the closing </form> tag and paste this into the body of your page.
newar the bottom of the apge is the spry script code:
<script type="text/javascript">
<!--
var sprytextfield1 = new Spry.Widget.ValidationTextField("sprytextfield1", "none", {validateOn:["blur"]});
var sprytextfield2 = new Spry.Widget.ValidationTextField("sprytextfield2", "email", {validateOn:["blur"]});
var sprytextarea1 = new Spry.Widget.ValidationTextarea("sprytextarea1", {validateOn:["blur"]});
var sprytextfield3 = new Spry.Widget.ValidationTextField("sprytextfield3", "none", {validateOn:["blur"], minChars:<?php echo $WAGLOBAL_Captcha_Characters; ?>, maxChars:<?php echo $WAGLOBAL_Captcha_Characters; ?>});
var sprytextfield4 = new Spry.Widget.ValidationTextField("sprytextfield4", "none", {validateOn:["blur"]});
//-->
</script>
copy this and paste into your page just before the closing </body> tag.