Whether you need a general overviews or specific facts on Hinduism, encyclopedias are a good place to start. When choosing an encyclopedia, ask yourself how broad your question is. If you're looking for basic information on countries where Hinduism is common, a general encyclopedia like Encyclopaedia Britannica would be a wise choice. If you want to know about marriage customs in a particular region, or a minor god or goddess, choose an encyclopedia that's entirely dedicated to India. You may also want to visit the reference rooms in Davis Library or the Undergraduate Library to look through reference books on the shelves. The reference rooms also have encyclopedias on specific topics like marriage and holidays; these could be helpful!

Several good general encyclopedias are:

Funk & Wagnalls New World Encyclopedia. New York: Funk & Wagnalls, 1996-.
Available electronically as Funk & Wagnalls New World Encyclopedia

The New Encyclopaedia Britannica. 15th ed. Chicago: Encyclopaedia Britannica, 2002.
Davis Reference, UL Reference, and many departmental libraries AE5 .E363 2002
Also available electronically as Britannica Online

Gale Virtual Reference Library contains several online books that may help you. Some that you may want to try are the Encyclopedia of Modern Asia, the Encyclopedia of Religion, and the Encyclopedia of Science and Religion. You can search all the books in this online library simultaneously.

 

Several encyclopedias focusing on Hinduism are:

Hiltebeitel, Alf. "Hinduism." Encyclopedia of Religion. Ed. Lindsay Jones. 2nd ed. 15 vols. Detroit : Macmillan Reference USA, 2005.
This scholarly article includes many cross-references to other related articles and an extensive bibliography. It takes a chronological approach to the subject matter, with coverage from the Indus Valley Civilization to the modern reformers who espouse monotheism, abandonment of the caste system, tolerance of other religions and agreement with modern science.
Davis Library Reference BL31 .E46 2005 v. 6

Lochtefeld, James G. The Illustrated Encyclopedia of Hinduism. New York: Rosen, 2002.
This book contains short, encyclopedic entries, arranged alphabetically by subject. It includes a scattering of illustrations, mainly black and white photographs. Clear and comprehensive, these two volumes cover the principal themes of Hinduism.
Davis Library Reference BL1105 .L63 2002 v.1-2

South Asian Folklore: An Encyclopedia. Ed. Margaret A. Mills, et al. New York: Routledge, 2003.
This scholarly encyclopedia contains many entries pertinent to Hinduism, such as "puja," "Hanuman," and "Goddesses, Hindu." The volume covers Afghanistan, Bangladesh, India, Nepal, Pakistan, and Sri Lanka. Some illustrations are included.
Davis Library Reference, Art Library Reference GR302 .S68 2003