How to add Javascript to banner?

Hey guys I am trying to add a javascript to display a idx search box(for real estate) over my banner image. It wont take up the whole width only a certain space. What is the best way to do this? Im not very experienced with wordpress or javascript but im great at following directions. Here is the script.
<script charset=”UTF-8″ type=”text/javascript” id=”idxwidgetsrc-36129″ src=”http://realestate.kansascityrealestate4sale.com/idx/quicksearchjs.php?widgetid=36129″></script&gt;
Thank you very much.
Taylor