Pankaj, the really genuine sites thatpay money to click and view ads are the nes that pay really really low money. So if you have plenty of patence and time, only then you gos for PTC work.
There are many sites who claim to pay money from $1 to upto$100 dollar just for clicking asingle link. STEER CLEAR of such sites as they are obviously fraud. No genuine site that pays people with the money they get from theior advertisers is going to pay you so much. The ratio just doesn't add up, so check first how much they are taking from their advertisers. If they are claiming to pay you more than what they are asking from advertisers, it is a 100% FRAUD site.
I am giving you a very good link below which will help you to search for a good and legitimate site. These people are taking extraordinary efforts to compile a list of genuine paying PTC sites. So before you think of joining any PTC site, check if its listed in the below mentioned directory.
Another good thing about it is that if a website is not listed in their directory, you can ask them to conduct investigations about it.