Are you looking for information on the web about a country or people group? There is a lot of secondary research citing the same basic sources, usually the CIA World Factbook, Peoplegroups, and the Ethnologue. The sites I have found most useful are Wikipedia, Joshua Project, and the World Atlas Project. They provide an overview and links to the relevant pages on other sites.
Wikipedia is a great place to begin your online research of a people group. Most people group articles will include information about the language, history, and culture of the people as well as links and sources. Joshua Project provides a graphical outline diagram that illustrates the affinity block, language, religion, and geographic links. A profile of the people group is given along with prayer requests and a picture of the people. Data related to their response to the gospel and current ministry among the people group is provided along with link to other useful websites. See also Peoplegroups for similar information and the Ethnologue for information regarding languages. The World Atlas Project provides many useful missions maps as well as country profiles that include missions implications. The CIA World Factbook provides useful information for each country in areas such as government, economy, technology, population, and more. It is useful to rank countries in areas such as infant mortality, GDP, and AIDS prevalence. Nation Master is a similar site that compares country information from the World Factbook and other sources.