NCERT Books are available in English and Hindi. We Tamil UPSC aspirants lack access to information. To Download NCERT Books in Tamil, there is no single stop solution.
It needs heavy work to translate into Tamil. Elambagavat IAS once said in his WhatsApp group that he had requested to translate many UPSC preparation books from English to Tamil. I’m not sure whether the request was accepted or not.
The method I’m suggesting now is just a temporary alternative. You can’t get the whole book in Tamil. But can translate the unknown paragraphs using this method.
We can use the technology to translate those English NCERT books in Tamil. If you don’t have NCERT books you can download it from http://www.gokuldeepak.com/ncert-books-free-download/