Wordpress adding thumbnails to the posts?

I installed timthumb and its working fine yet I cant figure out where to put the actually thumb in the code. I tried placing the timthumb call code before and after the title and many other places. I am trying to make it so the thumbnail is on the left side of the title and post description. Instead it is either under or over it.

Code I am using to call timthumb:

<?php // This will show the image and link the image to the post. Alter the width and height (in both places) to your needs. ?>
		<?php if ( get_post_meta($post->ID, 'thumb', true) ) { ?>
	<div class="postthumb">
		<a href="<?php the_permalink(); ?>" rel="bookmark" title="Permanent Link to <?php the_title(); ?>"><img src="<?php bloginfo('template_directory'); ?>/scripts/timthumb.php?src=<?php echo get_post_meta($post->ID, "thumb", $single = true); ?>&h=150&w=150&zc=1" alt="<?php the_title(); ?>" width="150" height="150" /></a>
	</div>
<?php } ?>

Code (markup):

Code I am using in my index template file:

<h3><a href="<?php the_permalink() ?>" rel="bookmark"><?php the_title(); ?></a></h3>

<?php the_excerpt(); ?>
<div class="details">
						<?php the_time('F j, Y'); ?> | <?php comments_popup_link(__('Leave comment'), __('1 Comment'), __('% Comments'));?> | Topic <?php the_category(', ') ?> | <a href="<?php echo get_permalink(); ?>" title="Read More">Read More</a>
					</div>

Code (markup):

Any help would be great thanks