Full Code of Registration Form that I posted blog article on http://extracatchy.net

registration-template.php

<?php  
/* 
Template Name: Login Page
*/
 
the_post()
get_header()
?>
 
<div class="wrapper">
	
	<?php
	$error= '';
	$success = '';
 
	global $wpdb, $PasswordHash, $current_user, $user_ID;
 
	if(isset($_POST['task']) && $_POST['task'] == 'register' ) {
 
		
		$password1 = $wpdb->escape(trim($_POST['password1']));
		$password2 = $wpdb->escape(trim($_POST['password2']));
		$first_name = $wpdb->escape(trim($_POST['first_name']));
		$last_name = $wpdb->escape(trim($_POST['last_name']));
		$email = $wpdb->escape(trim($_POST['email']));
		$username = $wpdb->escape(trim($_POST['username']));
		
		if( $email == "" || $password1 == "" || $password2 == "" || $username == "" || $first_name == "" || $last_name == "") {
			$error= 'Please don\'t leave the required fields.';
		} else if(!filter_var($email, FILTER_VALIDATE_EMAIL)) {
			$error= 'Invalid email address.';
		} else if(email_exists($email) ) {
			$error= 'Email already exist.';
		} else if($password1 <> $password2 ){
			$error= 'Password do not match.';		
		} else {
 
			$user_id = wp_insert_user( array ('first_name' => apply_filters('pre_user_first_name', $first_name), 'last_name' => apply_filters('pre_user_last_name', $last_name), 'user_pass' => apply_filters('pre_user_user_pass', $password1), 'user_login' => apply_filters('pre_user_user_login', $username), 'user_email' => apply_filters('pre_user_user_email', $email), 'role' => 'subscriber' ) );
			if( is_wp_error($user_id) ) {
				$error= 'Error on user creation.';
			} else {
				do_action('user_register', $user_id);
				
				$success = 'You\'re successfully register';
			}
			
		}
		
	}
	?>
 
        <!--display error/success message-->
	<div id="message">
		<?php 
			if(! empty($err) ) :
				echo '<p class="error">'.$err.'';
			endif;
		?>
		
		<?php 
			if(! empty($success) ) :
				echo '<p class="error">'.$success.'';
			endif;
		?>
	</div>
 
	<form method="post">
<h3>Don't have an account?<br /> Create one now.</h3>
<p><label>Last Name</label></p>
<p><input type="text" value="" name="last_name" id="last_name" /></p>
<p><label>First Name</label></p>
<p><input type="text" value="" name="first_name" id="first_name" /></p>
<p><label>Email</label></p>
<p><input type="text" value="" name="email" id="email" /></p>
<p><label>Username</label></p>
<p><input type="text" value="" name="username" id="username" /></p>
<p><label>Password</label></p>
<p><input type="password" value="" name="password1" id="password1" /></p>
<p><label>Password again</label></p>
<p><input type="password" value="" name="password2" id="password2" /></p>
<div class="alignleft"><p><?php if($sucess != "") { echo $sucess; } ?> <?php if($error!= "") { echo $error; } ?></p></div>
<button type="submit" name="btnregister" class="button" >Submit</button>
<input type="hidden" name="task" value="register" />
</form>
 
</div>
<?php get_footer() ?>