var mess = new Array(
'<img src="images/masthead/sold1.jpg" width="521" height="222" alt="" border="0">',
'<img src="images/masthead/sold2.jpg" width="521" height="222" alt="" border="0">',
'<img src="images/masthead/home1.jpg" width="521" height="222" alt="" border="0">',
'<img src="images/masthead/home2.jpg" width="521" height="222" alt="" border="0">',
'<img src="images/masthead/home3.jpg" width="521" height="222" alt="" border="0">');
var max = mess.length;
var num = Math.floor((Math.random() * max));
document.writeln(mess[num]);