Adding Lines between Posts

I want to put lines between my posts on main page, like this:

Image

Currently in index.php is:

<table cellpadding="20" cellspacing="20" border="0"> 

<?php
$col = 0;
$cols_per_row = 2;
while (have_posts()) : the_post();
  if($col == 0) echo '<tr>';
  ?>
  <td class="column'<?php echo $col; ?>" style="vertical-align: top">
  <div class="post" id="post-'<?php the_ID(); ?>'">
	<b><h2><a href="<?php the_permalink(); ?>" rel="bookmark" title="<?php the_title(); ?>"><?php the_title(); ?></a></h2></b>
	<div class="descr"><?php the_time('l, F jS Y, G:i a T'); ?></div>
	<div class="entry">
	  <?php the_content('Read the rest of this entry &raquo;'); ?>
<a href="<?php the_permalink(); ?>"
<img src="http://www.tamileelamonline.com/wp-content/uploads/fullstory1.png" ALIGN="right" WIDTH="95" HEIGNT= "40" />
</a>
	</div>

<br /><br /><br />
  </div>
  <td>
  <?php
  if($col++ >= $cols_per_row){
	$col = 0;
	echo '</tr>';
  }
endwhile;
?>

</TD>
</table>