Adding footers to posts?

Here is a quick solution for you:

on the page or post you want to add a post footer create a new custom field named post_footer and in the value add the footer content.

then paste this code in your theme’s functions.php file

add_filter('the_content',`my_post_footer`,99);
function my_post_footer($content){
   global $post;
   $footer = get_post_meta($post->ID,'post_footer',true);
   if ($footer){
      return $content . $footer;
   }
   return $content
}

and you are done!
This way you can have different footers on each page/post and none at all if you don’t want it.