var baseURL = 'http://s10.photobucket.com/albums/a109/Nancy12345/nancysavatar/';
var avNo = 8;

for(t=0; t<document.images.length; t++)
{
if(document.images[t].src.match('nancysavatar'))
{
document.images[t].src = baseURL+(Math.floor(Math.random()*avNo)+1)+'.jpg';
}
}