American Institute of Philanthropy
www.charitywatch.org

American Liberty Partnership
www.libertyunites.org

Better Business Bureau Wise Giving Alliance
www.give.org

Direct Marketing Association Mail Preference Service
www.the-dma.org/consumers/offmailinglist.html

Federal Trade Commission's National Do Not Call Registry
www.ftc.gov/donotcall

GuideStar
www.guidestar.org

Independent Sector
www.independentsector.org

Internet Non-Profit Center
www.nonprofits.org

IRS Search for Tax Exempt Organizations
www.irs.gov/plain/bus_info/eo/eosearch.html

National Association of State Charity Officials
www.nasconet.org

National Center for Charity Statistics
www.nccs.urban.org