In need of help on simple PHP script - Very new at this

[jlmartin1978]

I had a friend of mine make this php code for me. Im still trying to learn all of the ends and outs of it. What I am looking to do is #1, ad a code to allow the information provided to be emailed to me after the submitter has completed the form, and #2, change the code for looking for identical ip’s to block submitters, to looking for identical GLVAR numbers to block submitters. Im not 100% sure where to make these changes in the lines of code without messing everything up. Any help would be greatly appreciated.

[php]<?php
include(‘database/config.php’);
include(‘database/database.php’);

$err = '';

if(isset($_POST['submit'])){		

	$first = addslashes(trim($_POST['first']));	
	$last = addslashes(trim($_POST['last']));	
	$glvar = addslashes(trim($_POST['glvar']));
	$ip = isset($_SERVER['HTTP_X_FORWARDED_FOR']) ? $_SERVER['HTTP_X_FORWARDED_FOR'] : $_SERVER['REMOTE_ADDR'];	
	//echo $ip;

	 if(($first!='')&& ($last!='')&& ($glvar!='')){	

		$database = new Database(HOST, DATEBASE, USERNAME, PASSWORD);
		$allUsers = $database->select('user','ip','*',"ip = '".$ip."'");
		//echo $ip;		
		$checkIp = 0;			
		$checkIp = count($allUsers);	

		$userData = array(				
			'first_name' => $first,	
			'last_name' => $last,				
			'glvar_id' => $glvar,		
			'ip' => $ip,		
		);		

		if(!$checkIp) {			

			$database->insert('user',$userData);		
			header('location:thank-you.html'); 		

		} else {
			$err.='<p style="color:red">Ooops! You have already signed the petition</p>';		
	} else {	

		if($first=='') $err.='<p style="color:red">Your first name not empty</p>';	

		if($last=='') $err.='<p style="color:red">Your last name not empty</p>';	

		if($glvar=='') $err.='<p style="color:red">Your GLVAR ID not empty</p>';	
	}
}

?>[/php]