Below I will try and helpfully explain what is required for a UK citizen to get an Indian employment Visa but I may sometimes just start ranting, the process has scarred me and it still hurts to talk about.
Start on the outsourced visa processing website VFS Global, navigate your way to the online visa application form which is hosted on indianvisaonline.gov.in where you are greeted with an SSL error, a promising start - proceed anyway and hit the online visa reg button.
Now you should find yourself on visaservices.co.in. Take note of your Web and Application reference numbers, you"ll need both of them if you ever want to revisit any of this information. The next form is fairly painless and you can also book your appointment here. There is also the opportunity to do the entire application by post which I"d have preferred though there is very little information about how to go about this which is why I ended up going for a face to face interview.
All of the stuff you need to bring to the interview can be found here. If you have no qualification information then bring your CV along, bear in mind the photo size is not the same size as a passport photo.
If you're based in London then you've got a long way to go to find the processing centre, especially if you don"t have a car. It's about a 15 minute walk from Hounslow West station, it's a place a little like purgatory based just between Mordor and Guantamono Bay.
The people in the visa office are superbly helpful, especially given that they work in one of the lower pits of hell. Through faults of my own I had issues with both my CV and passport photos. They patiently waited for me to email my CV to them and let me retake my visa photo's free of charge, it was a really friendly service but very very busy. Do not expect to get seen at your appointed time.
After the interview, they take your passport and other documents and if there are any issues with your application and they will contact you by email to get them resolved. Once everything is done your passport and visa will be mailed back to you securely.
For a years employment to Visa I paid £320, it costs a UK national £100 more than any other country to get an employment visa in India. It turns out this is because the UK raised the costs for Indian nationals to get employment visas in the UK, India returned the favour by increasing their prices for UK nationals to get employment visas in India. It's great to see politicians continue to make logical decisions like this for the benefit of their citizens.