The UN libraries in New York, Geneva and Vienna provide a large amount of research guides on their respective websites. All these guides are now gathered in one place by the United Nations Regional Information Centre (UNRIC) in Brussels.
The research guides provide links to UN documents, websites of UN organisations, and other online resources. Most guides also contain an overview of relevant books and journals.
In addition, UNRIC offers its own UNRIC Library Backgrounders. There are Backgrounders on various topics as well as some specific countries and regions.