I have been frustrated over this, too. I found a link on Toyota's website regarding bluetooth syncing with mobile phones. See
http://toyota.letstalk.com/brands/toyota-bt/home.htm . Unfortunately, the iPhone is listed as incapable of transferring the address book. I had previously successfully transferred my address book from my Palm Treo. However, since I had literally hundreds of entries, I found it unmanageable to search from the Toyota's Navigation screen. I stupidly erased my entire address book from the Toyota and then attempted to transfer a smaller address book from my iPhone.
Groan ...
Message was edited by: giannitufolli