UMCOR (United Methodist Committee on relief) has established an account number for people who wish to give assistance to the people of Haiti. UMCOR workers are already on the ground in Haiti, and several were there even as the earthquake hit (we have a permanent field office in Port Au Prince.)
You can make a gift to UMCOR, and be assured that your money will go to help the people– UMCOR has the highest percentage of funds that pass through to the people needing assistance of any aid agency in the world.
Online donations can be made at http://secure.gbgmumc.org/donations/umcor/donate.cfm?code=418325&id=3018760 (this website is experiencing extremely high volume, so if you cannot access the site immediately please continue trying).