I am from Hong Kong and this is the link I received from NOKIA to upgrade my N900 to firmware 1.3.

www.nokia.com.hk/en/softwareupdate

According to NOKIA, you should download it from your pc first. By the way, you have to make a back up before you perform the software upgrade because it is actually not a upgrade. It reset your phone totally and then install the new firmware completely.

After the installation of firmware, it will ask you if you want to restore back up; and then you have to re-install all apps you have had downloaded and installed before.

Negative side is that this takes long time to complete. Positive side is that if you have any missing files, corrupted files in your recent phone. These should be fixed after the installation.

I have installed the 1.3 version for a month, it works fine for me so far.

Good luck!

TC