Non-governmental organizations are active in direct service around the world. They also prepare a variety of documents that can be useful in research—annual reports, country studies, position papers, and so on.
Some non-profits are devoted to research. These "think tanks" can be great sources.
Use the search engines below to search keywords across many IGO (inter-governmental organization) or NGO (non-governmental organization) websites. For example, a single search for "microfinance" using the Union of International Associations IGO search will find reports and research on this topic from USAID, World Bank, Asian Development Bank, and many more.