If you are not an Indian Citizen you will need a visa to visit India. Visa can be issued from your closest Indian Embassy / Consulate. 

Addresses for all the Indian consulates.

Customs :

The usual duty-free regulations apply for India; that is, one bottle of whisky and 200 cigarettes. 

Time :

India is 5 1/2 hours ahead of GMT/UTC, 4 1/2 hours behind Australian Eastern Standard Time and 10 1/2 hours ahead of American Eastern Standard Time. It is officially known as IST, Indian Standard Time and is consistent throughout the country.

Weather :

India has three major seasons: Summer, winter, and the monsoon.

The summer months (April - June) are hot in most parts of India. Temp remains in the range of 22C to 30C.

The winter months (November - March) are pleasant throughout India with bright sunny days. Winter remain pleasantly cool Temp between 12C to 20C.

The monsoons break at the beginning of June on the Southwest coast of India, and gradually break at all parts of the country, except southeastern areas. These areas receive most of their rainfall between mid-October and end-December. Temp remains in region of 18C to 22C.