Here are two articles that highlight the difficulties and dangers associated with foreign aid for the two countries of highest current interest, Afghanistan and Haiti.
In Afghanistan, the US Agency for International Development (USAID) has ignored its own procedures to throw money at the UN agency in charge of development projects there. Result: maybe $10-20 out of every $100 in aid actually make it to the announced destination; meanwhile, AID and the UN agency are the subjects of numerous reports on malfeasance.
As for Haiti, the Wall Street Journal's Bret Stephens argues that the worst thing we could do would be to provide more aid for reconstruction, once the humanitarian emergency is past. Haiti has received massive assistance for years, creating a culture of dependency and a corrupt and useless government. Any new aid 'surges' would only perpetuate those problems and make them even worse.