Visas 

All foreigners entering India need a visa.  You can print the form off the Internet, and apply by mail.  You have to send an application form, passport, 2 photographs, return postage and money order, then they usually send you your visa within a couple weeks, and you're all set to go. 

Currently (October 2010) in the UK, visas can be obtained through VFS Global. You'll find the information you need, plus application forms at http://in.vfsglobal.co.uk/  The forms have been causing headaches for a lot of people and more information can be found on the various forums.

The forms can be filled in and filed electronically, or you can print them off, complete them by hand and then post them with your passport, two photographs, return special delivery envelopes and payment. If you fill them in electronically, you can either then choose to print them and continue as above, or you can make an appointment at any of VFS's offices (in London these are in Hayes, Victoria and Clerkenwell. There are others in Manchester, Edinburgh, Birmingham) to take your passport, photos, and payment. If you choose this option, they will tell you when you're there which day your visa will be ready, and you return to collect it (it's usually a few days), or you can opt to have it returned to you by post, in which case you'll need to buy special delivery envelopes. 

Other countries have different contacts and different requirements for visas.

Indian Consulates

For further details check your local Indian Consulate website.  http://www.hcilondon.net for the UK.

To find your local one in the USA go to ... http://www.indolink.com/consulate/add...   For the rest of the world go to ... http://www.indiagateway.com/gov/consu...