On Dave Canterbury's youtube channel he is showing a silnylon tarp for around $60. He says it is just under 10x10. I think he said each side is 9'10". It has grommets and tieouts. I think it might be pretty good for hammocks, unfortuanately i wont be able to order one any time soon. Here is a link to the video:
http://www.youtube.com/watch?v=7GDbH...eature=g-all-u