// check for email address: look for [@] and [.]
function isEmail(elm){
if (isFilled(elm)== false) {
	return true;
	}
	else if (elm.value.indexOf("@") != "-1" &&
		elm.value.indexOf(".") != "-1" &&
		elm.value != ""){
	return true;
	}
	else return false;
	}
// Check for null and for empty
function isFilled(elm){
	if (elm.value == "" ||
		elm.value == null)
	return false;
	else return true;
	}
function isReady(form){
	if (isEmail(form.email) == false) {
	alert ("Please enter your full email address.");
	form.email.focus();
	return false;
	}
	if (isFilled(form.fname)== false) {
	alert("Please enter your First name.");
	form.fname.focus();
	return false;
	}
	if (isFilled(form.lname)== false) {
	alert("Please enter your Last name.");
	form.lname.focus();
	return false;
	}
	if (isFilled(form.streetaddress)== false) {
	alert("Please enter your Address.");
	form.streetaddress.focus();
	return false;
	}
	if ((form.B) == "other") {
	alert("Please enter your City.");
	form.B.focus();
	return false;
	}	
	if (isFilled(form.zip)== false) {
	alert("Please enter your zip.");
	form.zip.focus();
	return false;
	}
	  	if (document.entfrm.zip.value.length!=5){
      		alert("Invalid Zip Code (must be five digits)");
     	return false
   		}
		 
	if ((isFilled(form.phone1)== false && isFilled(form.phone2)== true) || (isFilled(form.phone1)== false && isFilled(form.phone3)== true)){
	alert("Please enter your areacode.");
	form.phone1.focus();
	return false;
	}
	if ((isFilled(form.phone2)== false && isFilled(form.phone1)== true) || (isFilled(form.phone2)== false && isFilled(form.phone3)== true)) {
	alert("Please enter your phone.");
	form.phone2.focus();
	return false;
	}
	if ((isFilled(form.phone3)== false && isFilled(form.phone2)== true) || (isFilled(form.phone3)== false && isFilled(form.phone1)== true)) {
	alert("Please enter your phone.");
	form.phone3.focus();
	return false;
	}
	
		
return true;
}
<!-- Limit the number of characters per textarea -->

function textCounter(field,cntfield,maxlimit) {
if (field.value.length > maxlimit) // if too long...trim it!
   field.value = field.value.substring(0, maxlimit);
// otherwise, update 'characters left' counter
else 
   cntfield.value = maxlimit - field.value.length;
}

function CheckNumeric()
{
   var key = window.event.keyCode;
   if ( key > 47 && key < 58 || key == 46 )
      return; 
   else
      window.event.returnValue = null; // otherwise, discard character
}