Inserting Adsense In Between Posts

Not sure if this has been covered anywhere on the Forum (at least I can’t find anything) However, I am trying to insert Adsense in-between posts. I have seen several places that refer to the process, except the line codes that I need to change are not located within my index.php file.

This is all I have within my WP Dashboard and cPanel

`<?php
/*
iBlogPro Copyright (C) 2008-2010 Andrew Powers, PageLines.com (andrew AT pagelines DOT com)

Licensed under the terms of GPL
*/

global $pagelines;

get_header();
if(pagelines(‘featureblog’) && VPRO) get_template_part(‘pro/template_feature’);
get_template_part(‘library/template_posts’);
get_footer();

?>

Thank you in advance for any information.