http://www.gsmworld.com/roaming/gsminfo/index.shtmlhttp://www.gsmworld.com/roaming/gsminfo/cou_il.shtmlLooks like having the 1800 band in Israel will keep you covered.
Does it work in the us as well?
If you would click on the link I gave and went to the US you would see that AT&T uses 850/1900 and T-Mobile uses 1900.