Apple Mac OSX Leopard 10.5 has some new wizard items for connecting to the internet using your bluetooth phone.
My N73 is already a great companion to my Nokia N800.
From the bluetooth menu (if bluetooth is not in the menu, go to System Preferences, click bluetooth and select 'show bluetooth status in the menu bar') select 'setup bluetooth device' and then select 'mobile phone'.
Originally with 10.4 on my Powerbook I had to manually select a modem script. This is not required with 10.5. The wizard selected Nokia phone for me.
When you get to the bit that asks about name and password and apn, enter: