PHP sessions

$login_check = mysql_num_rows($sql);
if ($login_check == "1") {
include ("membersarea.php");
}

$login_check = mysql_num_rows($sql);
if ($login_check == "1") {
?SESSION STUFF HERE?
include ("membersarea.php");
}

<?php
session_start();
if(isset($_POST['submit'])) {

// check from database

$login_check = mysql_num_rows($sql); 
if ($login_check == "1") { 
header("Location: members.php");
} else {
header("Location: error.php?e=1234");
}
}

<?php
session_start();
if (isset($_SESSION['username']) && isset($_SESSION['password'])) {
	$password = $_SESSION['password'];
	$username = $_SESSION['username'];
	//
	$query="SELECT * FROM users WHERE username='$usenrame'";
	$sql = mysql_query($query)or die(msql_error());
	$obj = mysql_fetch_object($sql);
	$email = $obj->email;
	$member_id = $obj->id;
	$member_name = $obj->username;
	//
	}
	if (!isset($_SESSION['username']) or !isset($_SESSION['password'])) {
	header("Location : http://namepros.com");
	}
}
?>

echo $email;