You could definitely do it via a custom field.

Depends on how your home page is set up. Presumably you would simply put in the URL you are wanting to redirect to. Then, in your home.php or front-page.php template you will replace the_permalink with your custom field.

When I do the custom field, do I use a href="http://www.debreardonsart.com/" or just http://www.debreardonsart.com for instance?

Here's the code I used:

function print_post_title() {
	global $post;
	$thePostID = $post->ID;
	$post_id = get_post($thePostID);
	$title = $post_id->post_title;
	$perm  = get_permalink($post_id);
	$post_keys = array(); $post_val  = array();
	$post_keys = get_post_custom_keys($thePostID);

	if (!empty($post_keys)) {
  	  foreach ($post_keys as $pkey) {
    	    if ($pkey=='url1' || $pkey=='title_url' || $pkey=='url_title') {
      	      $post_val = get_post_custom_values($pkey);
    	    }
  	  }
  	  if (empty($post_val)) {
    	    $link = $perm;
  	  } else {
    	    $link = $post_val[0];
  	  }
	} else {
  	  $link = $perm;
	}
	echo '<h2><a href="'.$link.'" rel="bookmark" title="'.$title.'">'.$title.'</a></h2>';
}

Then:

Once that’s done, open your index.php file and replace the standard code for printing titles…

<h2><a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title(); ?>"><?php the_title(); ?></a></h2>

… with a call to our newly created print_post_title() function:

<?php print_post_title() ?>

Now, whenever you feel like pointing one of your posts’ titles somewhere other than your own blog, just scroll down in your post editor and create or select a custom key called url1 or title_url or url_title and put the external URL in the value box.

I'm a little dense so I don't really know how to do that. The theme is this one: http://wpshower.com/themes/imbalance/

Thanks! Here is the home.php

<?php get_header(); ?> 

              <ul class="mcol">
              <?php if(have_posts()) : ?><?php while(have_posts()) : the_post(); ?>
              	<li class="article" id="post-<?php the_ID(); ?>">

			<?php
			if ( has_post_thumbnail() ) { ?>
                    	<?php 
                    	$imgsrcparam = array(
						'alt'	=> trim(strip_tags( $post->post_excerpt )),
						'title'	=> trim(strip_tags( $post->post_title )),
						);
                    	$thumbID = get_the_post_thumbnail( $post->ID, 'background', $imgsrcparam ); ?>
                        <div class="preview"><a href="<?php the_permalink() ?>"><?php echo "$thumbID"; ?></a></div>

                    
                    <?php } else {?>
                        <div class="preview"><a href="<?php the_permalink() ?>"><img src="<?php bloginfo('template_url'); ?>/images/default-thumbnail.jpg" alt="<?php the_title(); ?>" /></a></div>
                    <?php } ?>

                    <div class="article-over">
                      <?php print_post_title() ?>
                      <?php the_excerpt(); ?>
                      <div class="postmetadata">
                          Posted: <?php the_time(__('F jS, Y', 'kubrick')) ?>&nbsp;&#721;&nbsp;
                          <?php comments_popup_link(__('No Comments'), __('1 Comment'), __('% Comments'), '', __('Comments Closed') ); ?><br />
                          <?php printf(__('Filled under: %s'), get_the_category_list(', ')); ?>
                      </div>
                    </div>
                </li> <?php ?>
            <?php endwhile; ?>
            <?php else : ?>


            <?php endif; ?>
            </ul>

            <?php if(have_posts()) : ?><?php while(have_posts()) : the_post(); ?>
            <?php endwhile; ?>
            <?php else : ?>
                <h1 id="error"><?php _e("Sorry, but you are looking for something that isn&#8217;t here."); ?></h1>
            <?php endif; ?>


            <?php if(function_exists('wp_pagenavi')) { wp_pagenavi(); } ?>
<?php get_footer(); ?>

Thanks for your help. I will try and get back to you.