Massdrop has some more hammock stuff. This looks like a fairly inexpensive tank of a tarp. At 22oz I wouldn't want to carry it, but it would work for car camping. It's starting at $55.99 +$3.91 shipping and will go down to $47.99 +shipping if 12 people buy one.

Specs
210T Ripstop polyester fabric
Dimensions: 132 x 108 in (335 x 274 cm)
Weight: 22 oz (623 g)
Included
Aluminum anchor pins
Chord
Adjusters