These encyclopedias are good starting points. You won't cite them as a source but they can give you an overview and lead you to good sources.
Encyclopedia of Asian History (REF/DS/31)
Encyclopedia of India (REF/DS/405)
Encyclopedia of Modern Asia (REF/DS/4)
Kodansha Encyclopedia of Japan (REF/DS/805)
Southeast Asia: A Historical Encyclopedia (REF/DS/524)
Sage Reference
The University Libraries provides access to a wide variety of Sage Reference titles online. Find the collection under E-Books (Subject Encylopedias) in the University Libraries' list of databases.