My number is 571-279-3669
I would go to the dealer-ship to get a new one. Then they can program it for you.
Most auto parts stores sell them as well. Replacement should be no problem.
Looking for a Used Cobalt in your area?
CarGurus has 4,768 nationwide Cobalt listings starting at $2,000.
Search Chevrolet Cobalt Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Chevrolet Cobalt Experts