I have an F150 with a 2 inch trailer hitch mount. Here is what I bought, and it has been an excellent choice - most people that see it wish they had got it instead of whatever they bought. It was originally made by the company that makes the racks that go on the front of buses, but they sold their consumer division to Thule.
You can see it here:
http://www.bicycleracks.com/sttra.asp
or here:
http://www.thuleracks.com/thule/prod...d=8&sku=260120
It takes only about 5 seconds to load or unload the bike into the rack. I'm not sure how much they cost, I bought mine about 4 years ago.
The base unit fits 2 bikes, and you can add additional slide-on units for the 3rd and 4th bike.
I can email you some pictures.