I have a 2006 car with no Bluetooth in it. I have a Bluetooth thing that hooks onto my visor that cost $20. Works like a charm.
I also do not have a car with bluetooth. I use a little bluetooth headset that fits over one ear. The headset connects to the phone. If I am out running errands, I always have it on in case my wife calls. Also, if I know I'm going to be on the phone for awhile I wear it so I can keep my hands free.