eBay.
I sold two of my 5.0 Stangs on eBay, and they sold fast. One guy flew into LAX from AZ and drove the car back, and in the other transaction the guy flew in from St. Louis with his son and had the car shipped back. All i did was pick them up from the airport (i live 2 mins from LAX) and they both had cash in hand. Easy transactions.
Of course it does cost atleast $50 and up to list the car on ebay, then some minor additional fees once the vehicle sells, but it should sell pretty quick.