Read the purple book and do all the questions. That is the ONLY resource you need. Do not pay for apps or practice exams or anything else. Waste of money.
I've talked to a number of people at work who have failed the NCE. Some several times. The only thing I can recommend is to not let it get you down or reflect on you negatively as a test taker. After all, you made it through college so you can't be bad at standardized tests.
I used a book called The Counseling Encyclopedia, and passed on my first try.
You might also want to look into strategies for multiple choice exams. Like how to think through questions and eliminate answers so, even if you don't know the right choice you increase your odds of guessing right.
Yup our entire class used the Rosenthal text. However, the sample questions in here were much easier than what appeared on our actual exam.
You may be able to join Facebook groups if you look up some combination of North Carolina LCMHC/mental health/therapists etc. and post about NCE tutoring and see if anyone might be interested in your area. I would highly suggest this book and this website for studying. Good luck!!! :)