Books

I have these ACT study books in my office that you can check out, as follows:

Real Act Prep. Guide                                     McGraw-Hill's ACT Math
Kaplan's ACT Strategies                                Kaplan's ACT
Kaplan Prep Plus 2018                                  McGraw-Hill's ACT Math & Science
ACT for Dummies                                           Cracking the ACT- Princeton Review

Online

https://www.march2success.com/main/courses ;
 You can access ACT preparation, online practice tests with performance feedback.

https://www.petersons.com/
Free online practice tests

https://academy.act.org/
Absolutely free, personalized practice for the ACT
ACT Academy™ is a free online learning tool and test practice program designed to help you get the best score possible on the ACT test, and well on your way to college and career success.