Below is a list of Internet resources which I regularly find useful. The list is by no means exhaustive and is constantly being revised and updated. If you have other sites that you would like to make me aware of, let me encourage you to post them in the comments section so that I can incorporate them into the main list.
Maps, Statistics, and Other Data Resources: Websites that focus on publishing statistics or other quantifiable data, especially on Christianity or religion generally.
Denominational Homepages: These are the official or semi-official websites of major world or American denominations of Christianity (with a few additions). These sites host denomination specific news, official statements from important denominational prelates, congregational locators, and denomination specific resources.
Ecumenical Patriarch of Constantinople
Patriarch of Antioch
Patriarch of Alexandria
Patriarch of Jerusalem
Greek Orthodox Archdiocese of America
Antiochian Orthodox Christian Archdiocese of North America
Orthodox Church in America
Russian Orthodox Church Outside of Russia
The Standing Conference of Canonical Orthodox Bishops in the Americas
The Church of England / The Archbishop Canterbury
Evangelical Lutheran Church in America
Lutheran Church–Missouri Synod
Wisconsin Evangelical Lutheran Synod
Presbyterian Church (USA)
Presbyterian Church in America
Southern Baptist Convention
National Baptist Convention
American Baptist Churches (USA)
United Methodist Church
Assemblies of God (USA)
Christian Church (Disciples of Christ)
Mennonite Church (USA)
Friends World Committee For Consultation [Quakers]
Denominational Resources: These are denomination specific resources which may or may not be officially connected to the denominational hierarchy (where one is present) but which nevertheless provide important information or spiritual support to denominational adherents.
Oriental Orthodox and Syriac (Nestorian):
Assyrian International News Agency
History and Social Science Resources: The following links are primarily collections of primary source material from various points in history, both secular and religious.
Digital Public Library of America
Internet Classics Archive (MIT)
Christian Classics Ethereal Library
Early Christian Writings
The Avalon Project: Documents in Law, History, and Diplomacy (Yale)
Internet Medieval Sourcebook (Fordham)
Chronology of US Historical Documents (Oklahoma)
Making of America (Michigan)
Documenting the American South (North Carolina)
New Deal Network
American Civil War Manuscripts (Virginia Tech)
The Digital Librarian [Resource List]
General Religion Resources:
*Be aware that Adherents.com is made up of largely self-reported statistics, which often results in inflated numbers. Also pay special attention to the dates of statistics, as they are often older than materials found elsewhere.
^”Protestant” is used throughout in the colloquial rather than the academic sense and includes groups like Anglicanism which are not, strictly speaking, Protestant denominations.