Hi friends
There are lot of materials available for naplex.Main is Apha ,it gives a through outline of the portions covered in the exam,
study APHA two times, it is simple and for rememering you can go through prontopass.
calculations you can go through prontopass or mann $shroff
Instead of prontopass you can refer passnaplexnow review materials, but it is expensive.
There are lot of website
www.ritepassnaplex.yolasite.com
www.passnaplexnow.com
and ASHP pharmpreponline
good luck