The user bars in people's signatures? Go to Razzy's link, find the appropriate user bar, and rightclick > 'View Image'. Copy the url of the page (eg this because you own an RPL-260) and put it like this.
If you want to put your own images in your signature, you need hosting. PhyreFile and Photobucket are the most common, they will host most any picture for you so you can put it on a website, signature, etc.
Furthermore, this is Michael Jackson and he can do the moonwalk. Awwwwww yeahhhh.