With more than 1250 species of birds, India and South Asia are a paradise for bird watching. There are over 925 breeding species (~920 residents). The Indian birds belong to 16 groups called 'Orders', which are further divided into 'Families', 'Sub-families' and 'Genera'. For birding in India, 13 bio-geographical regions can be demarcated: Trans Himalayan, Western Himalayas, Eastern Himalayas, Desert, Semi-arid, Gangetic plain, Central India, Deccan Plateau, Western Ghats, Eastern Ghats, North East, Coasts and the Andaman Nicobar Islands. The Blue Peafowl (Pavo cristatus) is the national bird of India.

Indian birds:

•     Checklist of Birds (specifically for India): -From the World Conservation Monitoring Centre. Based on the Oriental Bird Club checklist.
•     --Most people in India still follow the checklist based on Ripley's, "Synopsis of the Birds of India and Pakistan".
•     Field Guides and Other Bird Books for the Region
•     -Including new and upcoming guides.
•     Trip Reports
•     -Updated fairly frequently
•     Birding Site Information (by region)
•     -Checklists, hotspots, etc.
•     Bird Call Mnemonics for the Indian Subcontinent (New)
•     -Collection of informal aids to remembering bird calls/songs.

Earlier Field Guides:

1. Salim Ali, S. Dillon Ripley, "Pictorial Guide to the Birds of the
Indian Subcontinent", 2nd ed., 1995, Oxford Univ. Press.
  This has color illustrations and very brief habitat and range
descriptions for all the approx. 1200 species. It is published by
OUP, UK. The second edition is now easily available in India.
Get it before it goes out of stock like the first edition.
This is the only book that has illustrations for all species.

2. Ali, "The Book of Indian Birds", 11th edition 1979, last
reprint 1992, Bombay Natural History Society and Oxford Univ. Press.
   A useful compact guide for the commoner birds of the subcontinent.
296 full descriptions with color plates. Also has useful apendices.
Not commonly stocked in the US but it might be possible to order copies
through OUP.

   A greatly enlarged and revised edition (12 ed.) is now readily available.
It describes and illustrates 538 species. These are illustrated in 64 new 
colour plates specially done by Carl d'silva.  Additional text has been taken 
from Dr Ali's field notes and edited by JC Daniel.

3. Ali, "Field Guide to the Birds of the Eastern Himalayas", last
reprint 1992, OUP.
   An excellent field guide. 366 color plates and 536 full descriptions.
Thus covers more species than 2 above. But the status and range
descriptions pertain only to the region of the Eastern Himalayas.
Available in the US. For ex. thru LA Audobon.

4. Martin Woodcock, "Collins Handguide to the Birds of the Indian
Sub-Continent", 1989, Dist. in the US by Viking Penguin, NY.
The 1995 edition is now available.
   Deals with commoner birds, 272 color illus. and brief descriptions.
Also has a synposis at the back that lists the name of all families and
briefly describes 273 more species with no illus.
 
5. Ben King et. al., "A Field Guide to the Birds of South-East Asia",
1991, Collins
   An excellent field guide dealing with birds of Burma, Indo-China
and Malaysia. Covers 1198 species with 869 color illus. with Peterson
style arrows. Even though I haven't counted exactly how many of these
are also seen in India there is a great deal of overlap. Collins says
it is out of print but it maybe in stock in some places. For ex.
LA Audobon.