There is a bill working it's way towards becoming a law in the U.S. that is designed to protect 'orphaned works' from copyright violations. The way the bill is written now basically says that a person can use an "orphaned" piece of work for whatever they want, as long as they make a 'reasonable' effort to find the original copyright holder. The law also limits the amount of damages that a person could receive if they were to prove that someone violated this law. As it is written now: an award for monetary relief
(including actual damages, statutory damages, costs, and attorney’s fees) may not be made, other than an order requiring the infringer to pay reasonable compensation for the use of the infringed work.
From what I understand, this bill also makes it the responsibility of the artist to prove that the infringer violated the law. If you ask me, that should be the other way around...
Here is a link to a copy of the bill.
http://www.publicknowledge.org/pdf/ow-act-2006.pdf