function checkEmailAddress(field) 
{
	var goodEmail = field.value.match(/\b(^(\S+@).+((\.com)|(\.net)|(\.edu)|(\.mil)|(\.gov)|(\.org)|(\..{2,2}))$)\b/gi);
	if (goodEmail)
	{
	  return true;
	} 
	else 
	{
	   alert('Please enter a valid e-mail address.')
	   return false;
	}
}
function checkForm(){
   var nmcheck = document.getElementById("customername");
   var emcheck = document.getElementById("customeremail");
   var pcheck = document.getElementById("productname");
   var qcheck = document.getElementById("productquestion");
   if (nmcheck.value == "") 
   {
      alert("Please enter your name.");
      return false;
   }   
   if (emcheck.value == "") 
   {
		alert("Please enter an e-mail address");
		return false;
   }
   if (pcheck.value == "")
   {
		alert("Please enter your product name");
		return false;
   }
   if (qcheck.value == "")
   {
		alert("Please enter your question");
		return false;
   }
   if (!checkEmailAddress(emcheck))
		return false;
	
	return true;
}