Start with CLIO to find books and journals in Columbia University library collections. (Use Educat for resources in the Teachers College Library.)
Then try WorldCat, the largest online catalog in the world, with over 100 million book and journal records.
To find dissertations, start with Proquest Digital Dissertations. Also check DART, Europe's E-theses portal.
Other essential resources include:
Ian Beilin, Philosophy & German Studies Librarian, igb4@columbia.edu
Yuusuf Caruso, Africana Studies Librarian (*excluding North Africa), caruso@columbia.edu
Michelle Chesner, Jewish Studies Librarian, mc3395@columbia.edu
Rob Davis, Slavic & East European Studies Librarian, rhd2106@columbia.edu
Gary Hausman, South Asian Studies Librarian, gjh2119@columbia.edu
Meredith Levin, Western European Humanities Librarian, mjl2209@columbia.edu (France, Italy, Low Countries, Scandinavia, Switzerland)
Peter Magierski, Middle Eastern & Islamic Studies Librarian (*including North Africa), pm2650@columbia.edu
Socrates Silva, Latin American & Iberian Studies Librarian, ss5000@columbia.edu
John Tofanelli, British & American History and Literature Librarian, jt628@columbia.edu
Jeffrey Wayno, Ancient & Medieval Studies/Classics/Religion Librarian, jmw2202@columbia.edu
Sarah Witte, Gender & Sexuality Studies Librarian, shs4@columbia.edu