images = new Array(2);

images[0] = "<a href='http://gobuffsgo.cstv.com'><img src='http://grfx.cstv.com/schools/wtam/graphics/wtam-07-masthd-right-1.jpg' width='488' height='110' alt='WTAM' border='0'></a>";

images[1] = "<a href='http://gobuffsgo.cstv.com'><img src='http://grfx.cstv.com/schools/wtam/graphics/wtam-07-masthd-right-2.jpg' width='488' height='110' alt='WTAM' border='0'></a>";

index = Math.floor(Math.random() * images.length);

document.write(images[index]);