The answer is here:

http://community.elgg.org/mod/groups/topicposts.php?topic=173314&group_guid=165444

this is my modified version of the register.php in views\default\account. You can modify below line 54 "    <!-- registration info -->" and insert whaterver you like, it will appear at the right hand side as the reg form appears at the left.. enjoy.

<?php

     /**
     * Elgg register form
     *
     * @package Elgg
     * @subpackage Core

     * @author Curverider Ltd

     * @link http://elgg.org/
     */
     
    $username = get_input('u');
    $email = get_input('e');
    $name = get_input('n');

    $admin_option = false;
    if (($_SESSION['user']->admin) && ($vars['show_admin']))
        $admin_option = true;
       
    $form_body = "<p><label>" . elgg_echo('name') . "<br />" . elgg_view('input/text' , array('internalname' => 'name', 'class' => "general-textarea", 'value' => $name)) . "</label><br />";
   
    $form_body .= "<label>" . elgg_echo('email') . "<br />" . elgg_view('input/text' , array('internalname' => 'email', 'class' => "general-textarea", 'value' => $email)) . "</label><br />";
    $form_body .= "<label>" . elgg_echo('username') . "<br />" . elgg_view('input/text' , array('internalname' => 'username', 'class' => "general-textarea", 'value' => $username)) . "</label><br />";
    $form_body .= "<label>" . elgg_echo('password') . "<br />" . elgg_view('input/password' , array('internalname' => 'password', 'class' => "general-textarea")) . "</label><br />";
    $form_body .= "<label>" . elgg_echo('passwordagain') . "<br />" . elgg_view('input/password' , array('internalname' => 'password2', 'class' => "general-textarea")) . "</label><br />";
   
    // Add captcha hook
    $form_body .= elgg_view('input/captcha');
   
    if ($admin_option)
        $form_body .= elgg_view('input/checkboxes', array('internalname' => "admin", 'options' => array(elgg_echo('admin_option'))));
   
    $form_body .= elgg_view('input/hidden', array('internalname' => 'friend_guid', 'value' => $vars['friend_guid']));
    $form_body .= elgg_view('input/hidden', array('internalname' => 'invitecode', 'value' => $vars['invitecode']));
    $form_body .= elgg_view('input/hidden', array('internalname' => 'action', 'value' => 'register'));
    $form_body .= elgg_view('input/submit', array('internalname' => 'submit', 'value' => elgg_echo('register'))) . "</p>";
?>

    <div style="width:300px; margin-left:0; float:left;">
    <div id="register-box">
    <h2><?php echo elgg_echo('register'); ?></h2>
    <?php echo elgg_view('input/form', array('action' => "{$vars['url']}action/register", 'body' => $form_body)) ?>
    </div>
 
    </div>
  
    <div style="width:323px; float:right;">
  
    <!-- registration info -->
    <div id="reg_info">
    <div id="reg_inside2">
    <p>Please fill everything out correctly, Provide a valid Email Address,  within moments you will receive an email in the email address you supplied to confirm your registration. After you confirm you will be able to login and access all features of the site.</p>
    <p><b style="color:#F00;">NOTE:</b> When choosing your username, make sure it is what you want. You will not be able to change this name once created! <br>Provide an easy to remember but hard to guess password to protect your online security; never store your password in an open location.</br> Your username makes up your profile i.e. http://www.phraternity.com/username.</p&gt;
    </div>

   
    <strong>Why Join Us?</strong>
    </div>
     
    <ul>
        <li id="inTouch">Stay in touch with friends & family</li>
        <li id="shareMedia">Share your photos albums, videos and bookmarks</li>
    <li id="createblog">Create Blogs and Pages and share</li>
        <li id="findOld">Find old friends and make new ones</li>
        <li id="itsFree">It's totally FREE!</li>
     </ul>
     <hr />
     <p class="noSpam"><strong>No Spam.</strong> Please read our <a href="<?php echo $vars['url']; ?>pg/expages/read/Privacy/">Privacy Policy</a>.</p>
  
    </div>

N.B: Backup your site before trying.

@ Agwalogu

I saw this only today. Good show.

I was wondering whether we can put the login form on the right side. Is that possible by any chance?