I have a Toyota Tacoma with a steel bumper that has the hole for a tow ball.
Looked for a ball mount fold-down bike rack and found the Swagman Ball Mount Rack (MSRP $139) on eBay for $69.95.
Heavy steel and very well-made. Super nice rack. Great price.

The eBay seller (eng68) carries a number of different Swagman hitch and ball racks
including 2" receiver and low mount racks from $62.95 and up.

This is the rack I got:
Swagman Bike Racks Home Page - Fold-Down Ball Mount Rack