maimi:
it's a G3 surf stick. does it make a difference?
I can't tell from here. If the surf stick is your internet connection, and the ip range is 192.168.1.x, and you have a 192.168.1.x localnet on the internet connection sharing device, you have a routing problem.
What ip does the surf stick get if using dhcp?
What ip does the ethernet shield get if using dhcp?
What ip is the ethernet device in the laptop assigned that the Arduino is connected to?