While the general public concerned about looting would probably prefer antiquity dealers to take simple steps to ensure that the goods they handle can be verified as kosher, incredibly they are actually debating in the antiquities blogosphere whether shooting to kill is an appropriate sanction for disturbing archaeological context for personal gain. J. Leuke on his ancient coin blogspot has what he sees as the solution to "Looting in Authoritarian Source Countries"
Rather than ineffectual import restrictions and inane blogs it seems to me the best solution is rather quite simple: Have those countries ban metal detecting. Why not embrace the authoritarian approach and create a solution matching the philosophy of the state. After the first few detectorists are shot looting will quickly cease.As I say, dealing with the no-questions-asked buying and selling of dugup antiquities involves nothing more than buyers just saying no, nothing more complex or violent.