The rules and regulations for foreigners to visit India change frequently.  Please review the following section, review the web site of the consulate and also call the consulate to confirm the requirements for obtaining your visa.  If you decide to go to the consulate in person, most definitely call ahead to confirm the timings.  The consulates follow their own holiday schedule which is a mix of Indian and US holidays.  Once again, please call ahead.

Also, when you call, confirm which consulate handles your jurisdiction/ state.

The Consular Wing (that deals in Visas) of the Indian Embassy in Washington DC is located at 2536 Massachusetts Avenue, NW  Washington, DC 20008
Phone:  (202) 939-7000 Fax: (202) 797-4693

Following are the addresses and contact information for Indian consulates in the United States:

Consulate General of India - New York
(Consular Jurisdiction: Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Puerto Rico, Rhode Island, Vermont, Virgin Islands)
3 East, 64th Street, New York, NY 10021
(Between Madison Ave & 5th Avenue)
Phone: (212) 774-0600 - Fax: Central (212) 861-3788 - Cable : CONGENDIA

Consulate General of India - San Francisco
(Consular Jurisdiction: Alaska, Arizona, California, Colorado, Hawaii, Idaho, Montana, Nebraska, New Mexico, Nevada, Oregon, Utah, Washington, Wyoming)
540 Arguello Boulevard San Francisco California 94118 USA
Phone:  (415) 668-0662  Fax:  (415) 668-9764

Consulate General of India - Chicago
(Consular Jurisdiction: Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, North Dakota, South Dakota, Wisconsin)
455, North City Front Plaza Drive, NBC Tower Bldg, Suite#850,
Chicago, Illinois - 60611.
Phone: (312) 595-0405 to 0410

Consulate General of India - Houston
(Consular Jurisdiction: Alabama, Arkansas, Florida, Georgia, Kansas, Louisiana, Mississippi, Oklahoma, Texas)
Three Post Oak Central
1990, Post Oak Boulevard Suite 600
Houston,TX-77056
Phone: (713) 626-2148/2149
Fax: (713) 626-2450 

US Consulates in India. 

U.S. Embassy – New Delhi
Shantipath, Chanakyapuri
New Delhi - 110021
Phone: 011-2419-8000
Fax: +91-11-2419-0017

Email addresses:
Nonimmigrant visa nivnd@state.gov
Immigrant visa IVND@state.gov
American Citizens Services acsnd@state.gov
General ndcentral@state.gov
Website: http://newdelhi.usembassy.gov/

Consulate General - Kolkata
5/1, Ho Chi Minh Sarani
Kolkata- 700071
Phone: 033-3984-2400
Fax: +91-33-2282-2335
Email: KolkataPAS@state.gov
http://kolkata.usconsulate.gov

Consulate General - Chennai
No. 220, Anna Salai
Chennai - 600006
Phone: 044-2811-2000
Email: chennaic@state.gov
http://chennai.usconsulate.gov

Consulate General - Mumbai
Lincoln House
78, Bhulabhai Desai Road
Mumbai - 400026
Phone: 022-2363-3611
Email: webmastermumbai@state.gov
http://mumbai.usconsulate.gov