coeur theme header

Hi, I have stumbled across the coeur theme and it appears to be perfect for my needs with one exception. I can alter the font colours and take away/change minor things to achieve my preferred look but I would like a large image displayed below the nav bar. It looks like the header are in this theme holds the title and tag line – which I want to keep! but I cant figure out how to get the image where i want it. Someone suggested creating a widget area below the navbar and inserting an image in the widget. How would I do that? Im afraid I am not a coder and when checking with firebug this seems one complicated theme. Any help would be appreciated.
Thanks