You have a static image that is controlling this. if you look at a default install template you will see that the logo is a smaller image aligned left the reset is a background image applied in the css.
For your header you will have to cut up the image and place it on a header that has a background color the same as the current green.
I would make 3 images the left the center & the right the left can be logo.gif or jpg the center cvan be >?? and would attach this to the tagline entry centered and the right you will have to edit the tpl_header.php adding say a logo2 entry with a class of forward to right align this.



