Hey guys,

So I've got a 1x1 grey pixel gif image that I want to use as an underline for every header. Current site - http://interactivesoundresource.com/orion/

url of said image is /orion/wp-content/themes/atahualpa/images/spacer.gif

I want it to look like www.supergiantgames.com - where even the Welcome bit and widgets have the image underline. Please help me!

Why not just use CSS for the line? You could put a 1px bottom border on the Headline Box in ATO>Style Posts & Pages as shown here.

You could do the same thing with the widget title box.