All your coaching posts have been deleted. If you want to waste time and money for coaching ask about it anywhere else; not here
If you are serious for GATE 2019 you can join GO classroom but only after leaving the mindset of coaching and being ready to work hard.
That's your view and you are entitled to your views. But atleast unhide my 2nd question which does not talk about coaching, It just states the thing that Im currently refering to as my notes https://gateoverflow.in/228750/cant-solve-previous-year-papers#a228753
Please man :(
Gateoverflow has its own book: http://book.gateoverflow.in
The book has been compiled by experts and has clickable links on questions which refer to this site for additional answers. By this month's end, the latest version would be up. You could also order a hard copy.
As far as the "best book" goes, no book can beat this one as this has been handcrafted by 100s of contributors(correct me if I am wrong).