The logo image path can be changed in the "css/template.css" file on line # 584. Look for:
#s5_logo {
float:left;
height:85px;
margin-bottom:15px;
margin-left:0;
margin-top:14px;
width:418px;
background: url(../images/Shape5_University_logo.png) no-repeat;}
You shouldn't need to do anything other than update the URL to point at whatever logo image you want to use.