Do you have the built in Phone in your radio? If so, getting bluetooth is fairly simple. I had a 2008 2LT with the Pioneer
audio system. It came stock with the Verizon phone connection through the radio.
There were some threads back in 2010-2012 on how to do the swap. The bluetooth / phone stuff was controlled by the Onstar module
that for me was in the rear package shelf.
I found one of the bluetooth modules from a 2009 Cobalt and swapped it into my 2008. Bluetooth worked pretty good. My cobalt is long gone but
I still have the Onstar bluetooth module I would part with $$. The part number for the module is 25983683.
Let me know if you (or anyone else is interested).