Kısaca :
<a href="http://www.site.com" title="title" target="_blank"><img border="0" src="http://www.site.com/img1.gif" alt="title" /></a>
<a href="http://www.site2.com" title="title" target="_blank"><img border="0" src="http://www.site.com/img2.gif" alt="title" /></a>
<a href="http://www.site3.com" title="title" target="_blank"><img border="0" src="http://www.site.com/img3.gif" alt="title" /></a>

bu 3 ünü rasgele gostermek istiyorum