South East Asia Earthquake and Psunami weblog is regularly updating its list of volunteer organizations and charities supporting Tsunami victims and seems to have the most complete list. It is also a clearinghouse for information on resources, aids, donations and helplines for Tsunami victims
New York Times has a comprehensive list of agencies in USA that are providing assistance to the Tsunami victims and are accepting contribution. Washington Post has a slightly different list of agencies to which one can donate money or supplies. The Post said that most groups are recommending donation of money (wherever possible).