I have the 8100 and you just have to follow the instructions in the car manual and go to the bluetooth menu on the phone. I do not know how to do the phonebook though. There have been other threads here on downloading directly to the car but I am not enough of a techie to figure it out.
THANKS, salsawonder, for your response. I'm also wondering whether I can use the Bluetooth technology to have my phone communicate with my PC and BitPim to transfer my own ringtones, etc.... but that's another forum.
Chas, You can use Bluetooth and Bitpim to transfer ringtones. I've got the 8100 and have been doing it. I got a D-Link Bluetooth USB adapter and it works fine once I updated the drivers. Try http://www.cellphonehacks.com or http://www.howardforums.com for more info.
Good news regarding the phone working with the Prius. I've got mine on order and am waiting impatiently!