The following are the banners you can link to us with. We've also provided the code's with which you can paste into your site and link to us with.

120x600 Banner (preview here)
<a href="<?=$this->config->item('base_url')?>" title="RetireAt21 - Young Entrepreneur, Business, Law and Accounting Help"><img src="<?=$this->config->item('base_url')?>images/ads/retire21-120x600.gif" alt="RetireAt21 Banner" /></a>;

125x125 Banner (preview here)
<a href="<?=$this->config->item('base_url')?>" title="RetireAt21 - Young Entrepreneur, Business, Law and Accounting Help"><img src="<?=$this->config->item('base_url')?>images/ads/retire21-125x125.gif" alt="RetireAt21 Banner" /></a>;

468x60 Banner (preview here)
<a href="<?=$this->config->item('base_url')?>" title="RetireAt21 - Young Entrepreneur, Business, Law and Accounting Help"><img src="<?=$this->config->item('base_url')?>images/ads/retire21-468x60.gif" alt="RetireAt21 Banner" /></a>;

728x90 Banner (preview here)
<a href="<?=$this->config->item('base_url')?>" title="RetireAt21 - Young Entrepreneur, Business, Law and Accounting Help"><img src="<?=$this->config->item('base_url')?>images/ads/retire21-728x90.gif" alt="RetireAt21 Banner" /></a>;