Add new row

Hi there,

I am now trying to add / remove rows for a couple of custom meta boxes withing the admin area.

Here is how I have created my meta boxes:

function add_feature_meta($post, $metabox)
{
	global $post;

	$show		 = '';

  	$custom = get_post_custom($post->ID);

	if (array_key_exists('show', $custom))
	{
		if ($custom["show"][0] == '1')
		{
			$show	= 'checked';
		}
	}

	include(MY_THEME_FOLDER . '/custom/featuremeta.php');

}

featuremeta.php contain the html:-

<div class="metaarea">
		<label for="title">Title</label>
		<input type="text" name="title" value='<?php echo $title; ?>'>
</div>
<div class="metaarea">
		<label for="subtitle">Description</label>
		<input type="text" name="subtitle" value='<?php echo $subtitle; ?>'>
</div>
<div class="metaarea">
    <label for="link">Link</label>
    <input type="text" name="link" value='<?php echo $link; ?>'>
</div>

I want to be able to add a row and save another set of data. I have seen this done and no idea how to get it working. I am trying not to use plugins as this is a learning exercise.

Thank you kind people