ok, in your stylesheet file, you scroll down until you get to this section
HTML Code:
/*sideboxes*/
.columnLeft {}
h3.leftBoxHeading, h3.leftBoxHeading a,
h3.rightBoxHeading, h3.rightBoxHeading a {
font-size: 1em;
color: #ffffff;
}
#manufacturersHeading, #currenciesHeading, #musicgenresHeading, #recordcompaniesHeading, #searchHeading, #search-headerHeading {
font-size: 0.9em;
color: #ffffff;
}
.leftBoxHeading, .centerBoxHeading, .rightBoxHeading {
margin: 0em;
background-color: black;
}
.leftBoxContainer, .rightBoxContainer {
margin: 0em;
border: 1px solid #5ABEE7;
border-bottom: 5px solid #5ABEE7;
margin-top: 1.5em;
}
.sideBoxContent {
border-top: 1px solid #5ABEE7;
background-color: black;
background-image: url(../images/cyber.gif);
padding: 0.4em;
}
then, under .sideBoxContent, you add
HTML Code:
background-image: url(../images/YOURBACKGROUNDIMAGE.gif);
the end