There are numerous important topics suggested by toppers and certain weightages are assigned to each topic as mentioned below.

https://engineering.careers360.com/articles/jee-main-2015-important-topics-books-know-from-experts

https://engineering.careers360.com/articles/jee-main-exam-pattern

There are abundant books available in the market, However some top Books for indepth Preparation are shared below.

Physics:- 

Concepts of Physics Vol I and II by H.C. Verma

.New Pattern JEE Problems: Physics by DC Pandey.

Chmeistry:-

Organic Chemistry by O.P. Tandon

Numerical Chemistry by P.Bahadur

Mathematics:-

Maths XI & XII by R.D. Sharma

All the above books have been recommended by various toppers.