Customize/HTML for 2012 Header

Ok, on my new site easyengrave.com I am trying to figure out the header and put it into a “pretty” state…

but I’m having some issues. And I think I might want to just do custom HTML. But how can I do that in a fashion that will not need to be changed every time I update wordpress. I do have a child theme for 2012, but I don’t think that alone will do what I want.

Also, when I do a banner in the wordpress admin page, the banner goes BELOW the navigation bar… which is, well, craziness to me.

What I’d really like to do is a banner/image at the very top and maybe a line of text below it.

Thank you.