Donations to relief in Haiti may be sent to the Salvation Army, which has low administration costs, insuring most of the money is actually used for help.

Another is The Clinton Foundation:
Clinton Foundation

This foundation, founded by former President Bill Clinton, UN Envoy to Haiti, is providing funds for immediate relief.
In Canada, the Clinton Giustra Sustainable Growth Initiative (Canada) is helping to raise funds via mobile text messaging for the relief effort in Haiti. 100% of donations will be directed to Haiti relief efforts.
Details at the above website.