Put the background image in #headerWrapper
Code:
#headerWrapper {
background-image: url(../images/yourbg.gif);
}
Load in /your_template/images/.
Load your logo file in the same place; naming it logo.gif will eliminate any other file editing for this (except for defining the height & width in header.php). You can position #logoWrapper with your stylesheet.
Put your text in the tagline define, and then position #tagline:
Code:
#tagline {
color:#000000; /*adjust to taste*/
font-size: 2em; /*adjust to taste*/
text-align : center;
vertical-align: middle;
position: absolute;
left: 123px; /*adjust to taste*/
top: 42px; /*adjust to taste*/
}
The position: absolute; allows the tagline to go anywhere on the page, even on top of other elements. Make #headerWrapper position: relative; so it will serve as a reference container for the tagline.