How to know, from where the clicks are being generated and on which ad placement the visitors are clicking? Is there any tool?
There's no way to know from where the clicks are coming from, at least a reliable one. You can use channels to see the most clicked Ads on your site, it's quite easy.
From analytics we can only know from where the user are comming not where they are clicking instead i hope google webmaster tool can help, which pages are being clicked more but it also can not define the particular ad position ...
you can create ad based on your site,[if you have site more than 1].. so you will know which have most click