I'm no pro at layers but here's an example:
<div id="logo" style="position:absolute; left:0px; top:1px; width: 255px; height: 68px;">
text you want to use<div>
Place your image where ever you want it on the site and use the above to put text over it. (I think anyway). You'll have to adjust the absolute positions depending on where your image is.
Be careful though... remember people have different sized browsers! Ie if you put your image inside a table with percentage width the text may not cover it..
play around with it, sure you'll work it out!