The code was removed due to its size and remember not to post URLs. Ill provide an example so you may get the jist of what to do:
CSS:
.myRollOver, .myRollOver:visited {
background-image: url('yourImage.gif'); /* This would be the normal image */
}
.myRollOver span {
text-indent: -5000px;
}
.myRollOver:hover, .myRollOver:active {
background-image: url('yourImage2.gif'); /* This would be the roll over image */
}
HTML:
<!-- Set the class to be the same as the css above -->
<a href="#" class="myRollOver"><span>Text Link</span></a>
This is a very bare bones example, you would most likely want to setup width and height (dont forget to set the display type to block (display: block;), which will allow for the dimensions to be set.
Also the span tag is in there if you wanted to hide the text, see the text-indent line in the css.