function validateForm()
{
if (document.getElementById("fname").value==""){
                alert("Please enter your firstname");
                document.getElementById("fname").focus();
                return false;
  }
if (document.getElementById("lname").value==""){
                alert("Please enter your lastname");
                document.getElementById("lname").focus();
                return false;
}
if (isNaN(document.getElementById("postcode").value)){
                alert("Your postcode is not valid");
                document.getElementById("postcode").focus();
                return false;
}
if (document.getElementById("email").value.indexOf("@")==-1){
    alert("The Email Address you entered was Invalid");
    document.getElementById("email").focus();
    return false;
  }
if (document.getElementById("email").value.indexOf(".")==-1){
    alert("The Email Address you entered was Invalid");
    document.getElementById("email").focus();
    return false;
  }
}