www.google.com error

Hi, i live in Australia and i cannot access www.google.com

If i type "www.google.com" into the address bar in either firefox or IE, an error permantently comes up saying "Firefox can't establish a connection to the server at www.google.com"

The only way i can access google is to type in www.google.com.au

Is there anything i can do so i can normally type in "www.google.com" and let google automatically re-direct me to ".au" becuase this error doesn't allow me to access google adsense as it needs to be "google.com".

Cheers.

p.s. about a month ago, i could normally access google by typing www.google.com but now i cannot.