Most are common sense but good to keep in mind
Avoid Newly-Formed Charities and Give To An Established Charity That Has Worked In Haiti - Establishing a new charity is hard enough, but in a crisis, the odds of succeeding are slim to none. Think of it this way: would you entrust all your savings in a financial firm that just opened, doesn't even have stationery, and whose employees have no experience in investing money? Doubtful. Find a charity with a proven track record of success in providing disaster relief and one that has worked in Haiti. Start with the list of charities provided on Charity Navigator and if a group you are considering supporting isn’t there, then take the time to thoroughly research it before making a gift.
Do Not Give To The Haiti Government – Haiti is known to be a corrupt country. And news reports post earthquake indicate that the government is pretty much not functioning. If that isn’t enough reason not to give directly to the Haiti government, then consider the fact that contributions to foreign governments are not tax deductible.
http://blog.charitynavigator.org/2010/01/tips-tips-and-more-tips-for-funding.html