Brill's New Pauly : encyclopaedia of the ancient world : Classical tradition
Encyclopaedia Judaica
Encyclopedia of the Dead Sea scrolls
Oxford encyclopedia of archaeology in the Near East
Who's Who in Ancient Egypt
Who's Who in The Roman World
A Guide to the Ancient World
Late Antiquity: A Guide to the Postclassical World
Academic Search Complete is a database of academic journals, magazines, and other scholarly resources, covering a wide range of subjects across the humanities, sciences, and social sciences. It's a great starting point for research, especially with its inclusion of many open access publications.
JSTOR provides comprehensive access to peer-reviewed scholarly journals, books, and primary sources from various disciplines within the humanities and social sciences.