Try the default set up address http://192.168.0.1/start.htm
this should connect and then you can modify the settings yourself
Assuming that the router is new - you may need to reset it by pressing the button on it in for 10secs
Once you are connected - you then have to set it up for your account - PPPoA etc (Which, presumably you know)
most (if not all) Netgear Routers have a set up wizard to help