I just passed A+ Core Hardware(602)and low passed (562) A+ OS
I spent one week to prepare A+ Core Hardware and two weeks in A+ OS
I read three books (borrowed it from San Jose public library)
A+ certification for dummies / by Ron Gilster
All-in-one A+ certification exam guide / Michael Meyers, Scott Jernigan. McGraw-Hill/Osborne, c2003.
The question in these two book is too easy and NO question from this book in the test.
I couldn't say it's useless because it gave me some fundamental idea.
A+ practice questions Exam cram 2 / Charles J. Brooks. [Indianapolis, IN.] : Que, c2004
This book help me a lot. 
The question in Hardware is easy but too much questions about NetWork(almost 30 questions).
The question in OS is very tricky and hard.
Some question I have never seen from book and internet free test.
But.....I passed......
