Positioning div tags to stay with centered background image

My problem seems pretty simple but I am having trouble finding a solution.

Please see this page at http://www.yourdesignateddesigner.com/Echostar.html


I have a background image that is centered on the page. I have quite a few apDiv layers that I need positioned exactly the way I see them layed out in dreamweaver's design view. I am fairly new with div and css, as you can probably tell.

Here's the code for one of my div layers:

<div id="apDiv4"><img src="Echostar Site/echostar_logo copy.gif" width="154" height="45" align="absmiddle" /></div>