There are actually 2 instances of tile_back.jpg in your css:
Code:
h2.centerBoxHeading, .productListing-rowheading {
margin: 0em;
background-image: url(../images/tile_back.jpg);
font-size: 1em;
color: #ffffff;
padding: 0.5em 0.2em;
border-bottom: 1px solid #9a9a9a;
and
Code:
#navEZPagesTop {
background-image: url(../images/tile_back.jpg);
background-repeat: repeat-x;
border: 1px solid #9a9a9a;
Change these to your image file name and all should be well...
These were in stylesheet_new.css...you should convert to a template based on one and not the combo classic as you have.