Here are some useful links we've found for nonprofit organizations.
Alliance for Nonprofit Management
The Alliance for Nonprofit Management is the professional association of individuals and organizations devoted to improving the management and governance capacity of nonprofits - to assist nonprofits in fulfilling their mission. The Alliance is a learning community that promotes quality in nonprofit capacity building. The Alliance convenes a major annual conference, networks colleagues year-round online, and provides member discounts on books and other publications. The Alliance provides visibility to its members in the online “Find a Consultant or Service Provider” directory, the People of Color Roster, and the print membership directory.
Pennsylvania Bureau of Charitable Organizations
The Bureau of Charitable Organizations administers the state's charitable solicitation law. They also maintain registration and financial information on over 9,500 charities soliciting in the Commonwealth, as well as 377 professional solicitors and fundraising counsels.
GuideStar is the leader in providing comprehensive data on more than 1.5 million nonprofit organizations, connecting them with donors, foundations, businesses, and governing agencies in a nationwide community of giving. Each day, about 20,000 people find answers using GuideStar. The information we provide contains searchable data from IRS Forms 990 and the IRS Business Master File, including comprehensive facts on employee compensation and grant activity. With our new eDocs service, nonprofits can add their annual reports, audited financial statements, letters of determination, and other documents to our growing store of information, making GuideStar a more powerful tool than ever.
Idealist.org is a website that facilitates connections between individuals and institutions that are interested in improving their communities. Over 57,000 nonprofit organizations from more than 180 countries have created profiles on Idealist.org. They use these profiles to list information about their missions, programs, services, and opportunities.
Pennsylvania Association of Nonprofit Organizations
PANO is the statewide membership organization serving and advancing the charitable nonprofit sector through leadership, advocacy, education and services in order to improve the quality of life in Pennsylvania.
Nonprofit Resources from the Carnegie Library of Pittsburgh
A variety of additional links to help you out.