Open up /skins/whatever-skin-you're-using/_main.php. Find the code that displays the time, category and words. (Search the file for 'Permalink' if you're having a hard time finding the right section.) Then drop in this code:

<a href="<?php $Blog->disp( 'blogurl', 'raw' ) ?>?author=<?php the_author_ID() ?>" title="<?php echo T_('Browse all posts by this author') ?>"><?php $Item->Author->prefered_name() ?></a>

That will make the author's name a link, which makes the blog display only that author's posts. If you just want their name to be in plain text, then use this code:

<?php $Item->Author->prefered_name() ?>

Thanks! Got it working just great! :D