Why can you not do it?
Does it give you an error ?
You can't link to an image on your PC. It has to have a URL (i.e
www.siliconhell.com.... ). You can link to one anywhere else. If your ISP (who you get your internet access from) give you personal webspace, you can load it up there and link to it from the Avatar control panel in the Your Profile Settings. Your link would look like
http://www.yourwebsite.com/imagename
Hope that this helps you out
MadCat