Ok, If I was gonna use my Camaro for haulin bikes (I have my Aveo for that) I would get the small 1 1/4" receiver hitch put on. It wont detract as much from the car like a roof rack or large reciever. Then put on one of these. I have this and so easy to use, just throw the bike on and lock it down. Have to use a cable lock though if you want to keep it secure.
http://www.performancebike.com/bikes..._400007_400170 The other advantage is that it keeps from getting crap all over the roof and decreases the risk of scratching up your car or doing the imfamous, "i forgot the bikes were on there" when you pull into the garage.