Looks okay to me.
About the only thing I would change is this line:
If Request.Form="" Then
I would, instead, specifically use the suibmit button:
If Trim( Request.Form("Submit") ) = "" Then
But I doubt that really matters.
To check that the HTML you are creating is correct, you should add in one DEBUG line:
sEmailText = sEmailText & "</html>"
Response.Write "DEBUG sEmailText:<hr/>" & Replace(sEmailText,"<","<") & "<hr/>"
If that debug looks okay, then it must be a problem in the Configuration. And the only people who can help with that would be those at "mail.reliablesite.net", the email service you are trying to use.