You can donate to the American Red Cross International fund online. You can even make your payment through Amazon.
You can donate through the American Jewish World Service:
The Catholic Relief fund:
The Clinton Foundation has been especially active in Haiti:
The Salvation Army:
Medecins San Frontieres:
The International Rescue Committee
There are many other worthy organizations. Remember that these organizations need to maintain emergency funds for the next emergency; so there is no need to worry about too many donations. Do not restrict your donation to Haiti. The next disaster could be here.