I just went through this. Just bought a brand new radio that has Bluetooth streaming, hands free calling, and IPod connections , for @$ 130.00. It works so well, that I put them in three of my cars last week! The hands free phone feature itself is worth the price. Highly recommend this route over going with grom adapters and such. Those are geared more towards newer radios that have Nav systems and such or for people who want to keep their original head unit.
Alpine CDE-133BT CD receiver at Crutchfield.com