Think Tanks, Non-governmental Organizations (NGOs) and Inter-governmental Organizations (IGOs) publish original research (often free on the Web) as well as provide useful up-to-date news on topics of global and national interest. Much of the content is deep within the respective sites, so a Google search may not bring up the best reports. Some non-profit organizations have strong political ties and may provide a biased view of a particular issue. While some think tanks self-identify on the political spectrum, designation of the bias of others is somewhat subjective.
|Think Tank Scholar or Corporate Consultant? It Depends on the Day
NYTimes.com 8 August 2016
The Think Tank Spectrum in Extra, a publication of FAIR (Fairness and Accuracy in Reporting), categorizes some of the best-known Think Tanks as 'conservative', 'progressive', or 'centrist'. The 2015 Global Go To Think Tank Index (GGTTI), published annually by the University of Pennsylvania, ranks Think Tanks in various ways. Another source, FindTheData, provides a chart comparing revenue, expenses and contributions of approximately 230 organizations, and allows sorting by political affiliation.
The subscription database CIAO: Columbia international affairs online searches within many well-known think tanks, with a focus on International Relations. The search box below is a custom search created in Google; it is in no way complete, but may provide a useful starting point.