Hacked?

Hi,

I would appreciate any help.

I wasn’t aware that my site was hacked (all working fine) but when I checked the source of my page, I noticed that below the footer there was the following:

<!– google –><font style=”position: absolute;overflow: hidden;height: 0;width: 0″>
xeex71701

followed by a bunch of links.

It seems that someone has hacked me but I’m not really seeing how it’s actually effecting my site.
Either way, I want to get rid of it, but am having trouble finding the rogue file/script.
Any idea how I can track it down and kill it?

Thanks!