The Vatican (w2.vatican.va/content/vatican/en.html)
United States Conference of Catholic Bishops (www.usccb.org/)
Archdiocese of Portland (archdpdx.org)
Catholic Research Resources Alliance (www.catholicresearch.net)
The CRRA provides enduring global access to Catholic research resources in the Americas, beginning with access to the rare, unique and uncommon research materials.
Center for Applied Research in the Apostolate (cara.georgetown.edu)
CARA is a national, non-profit, Georgetown University affiliated research center that conducts social scientific studies about the Catholic Church. A great source for Catholic statistics.
Christian Classics Ethereal Library (www.ccel.org)
The mission of CCEL is to build up the church by making classic Christian literature widely available and promoting its use for edification and study by interested Christians, seekers and scholars. Searchable database of the Church Fathers – highly recommended.
Religion on the Web (www.wabashcenter.wabash.edu/resources/guide-headings.aspx)
A selective, annotated guide to a wide variety of electronic resources of interest to those who are involved in the study and practice of religion, including syllabi, electronic texts, electronic journals, web sites, bibliographies, liturgies, reference resources, and software.
Google Scholar (scholar.google.com)
Google Scholar provides a simple way to broadly search for scholarly literature.