Tell Congress to join the rest of the world in making the right decision in telling Israel to stop attacking Lebanon.
Here's a site to monitor your Congressman's actions. Includes money they receive from Lobby Groups, votes on bills, floor speeches, and more.
http://www.govtrack.us/
There will be another petition coming out regarding AIPAC (American Israeli Public Affairs Committee) who is a very strong government lobby group and the reason why the U.S. strongly supports Israel. Here's some information on them.
Info on AIPAC
http://en.wikipedia.org/wiki/AIPAC