Just as a follow-up, I had a go at putting this code in the header.php file (within the div id=”headerimg” tags):
<img src=”<?php bloginfo(‘stylesheet_directory’); ?>/images/amelieheader.jpg”>
…and it showed the image. However, is this “correct” syntax? Is there a better way to do it? Because it seems that the div id tag linking to headerimg is there for a reason.