Right click -> copy image url.
Inspect that bitch.
Code:
http://images.tibiacast.com/signature?username=Luls&style=default
What, that seems simple.. Hmm.
Hey, it worked! All I did was change the name in the link.
You've gotta learn how to figure out simple things like this on a computer if you want to survive living in the internet. You only live once.