Featured Images in Category Templates

So, I’ve read the documentation and understand how to call the image (more or less), but I’m a little confused as to how to implement it in the category archives page.

This is what is there right now (before messing with the featured image), which is the default Twentyten set-up for the Category Template:

<?php
$category_description = category_description();
if ( ! empty( $category_description ) )
echo ‘<div class=”archive-meta”>’ . $category_description . ‘</div>’;

/* Run the loop for the category page to output the posts.
* If you want to overload this in a child theme then include a file
* called loop-category.php and that will be used instead.
*/
get_template_part( ‘loop’, ‘category’);
?>

I’m assuming this (from the Category Template) is not where I call the thumbnail, but I instead have to call it in some other php file. Is that correct? The main loop file, I’m guessing? If so, where in the main loop file do I put it? I only want the excerpt and featured image on the Category pages, so does that change anything I edit in the loop?

Thanks for any help.