Google Adsense is one of the easiest way to earn a regular income , for a popular website with a lot of traffic. There very few alternatives in India, that pay as well as Adsense. Yahoo has a program similar to Adsense, but it is only open to US publishers at present .

If you already have a useful website and you apply for Google Adsense, you will be usually approved within 2-3 days. You can then login into your account, copy and paste the Adsense code on all pages of your website.  Relevant ads will be visible to  visitors to your website within 24 hours. You will be paid per click and the amount depends on how much the advertisers have bid for a click on that particular advertisement through Google Adwords. The minimum bid amount is US$0.01 and can be multiple dollars for expensive and competitive product categories. You may also be paid on a per page view basis (CPM) , if  an advertiser has selected your website for displaying their advertisement.

Google has  made it possible for you to earn a regular income by writing on favorite subject . This is possible through their Adsense program .  Google has a large number of advertisers in India , who will pay to advertise on your website . Inside Google India is a article from Business Today , which part of the India Today group. Joining the program is FREE, they have sent payments monthly for more than 2 years, and you can earn more money than any work at home scheme in India. You can choose to receive payments in Indian Rupees or  US Dollars. Google has recently opened sales offices in Mumbai and Delhi

The websites of  Times of India (Indiatimes), Indian Express and Outlook earn money from advertising through Adsense. This is how they provide free information on their  website.  Unlike most other internet advertising programs, Adsense is open even to small websites. . Some website owners  from India earn a lot of money from Adsense - some earn more than US$5,000 (approx. Rs 2.2 lakh) per month. Indian earning more than US$5000 per month from Adsense 

You can start by opening  your  own easy to use website-  blog FREE at  blogger . If  you post information regularly on topics of your interest, you will get regular visitors looking for relevant information.  A good Indian blog  for reference is  Youth Curry  After your blog has 10-15 posts , you can apply to Google Adsense.

If your website is as per the terms and conditions of Google Adsense, you will be  accepted within 2-3 days. You will get a confirmation email from Google and you can then include your Adsense code in your blog.

Your Adsense earnings will depend on the number of visitors to your website. In general, greater the number of visitors, higher your revenue. The number of visitors will depend on the subject of  your website and how often you post. If you post regularly, your website will get more traffic.  Also topics like  film stars, sports (cricket, Sania), TV shows (Indian Idol) are more popular in India.  Finance, stock markets, medical and healthcare related topics also pay well.

Adsense has an attractive referral scheme. If  a visitor to your website joins Adsense by clicking on the referral button on your website, you will earn US$100 as soon as your referral earns $100. Adsense Referral Program details.  However, please ensure that your websites should comply with the terms and conditions. If any fraud is detected, they will immediately disable your Adsense account and you will lose all your earnings and be banned for life.

To learn how to increase traffic to your blog, you should join various forums on internet marketing.  You can join most forums for free, you only need an email address. You can also post any question you have on these forums, usually experienced people will help you out.You can also earn money from joining revenue sharing forums like Digital Point . After you have made more than 50 posts in this forum,  you will earn a portion of the revenue from the Adsense ads shown on the forum. Some members of the forum earn up to US$50 a month by posting and answering questions and comments

A list of sites where AdSense publisher can use their own AdSense IDs to earn money is available.

http://www.admoolah.com/blog/index.php/adsense-revenue-sharing-sites/