Page layout change - adding an image

[Paul.nz]

Hi all.
I want to add an image near the top of the page, above the list of menu items.  Which script sets up the major page layout? Can I just add some html in there?

SMF 2.0.15.

[Arantor]

That would be Themes/default/index.template.php

As it's PHP, you can't just shove HTML in there, you have to put it in the right place inside the quote marks...