IMO, it is a stage.
I've got a really laid back DS, who went through this stage of everything had to be exactly his way, his plans, him first... from about age 4.5 to 5.5. Luckily it is a stage. He is almost 6 now and realizes the world does not revolve around him and rules are not always black and white.
I've got a DD who will be 4 in 47 days (yes, she is counting down) and she is so strong willed it makes me cringe. I am not looking forward to the fours. Then again, she is also independent and confident, so you gotta take the "good with the bad" kwim?
IMO, if this has developed around age 4 for your DD, and she wasn't so much this way beforehand, then I would skip the books and just ride out the stage. If she was always this way, and it is just more exaggerated now that she is 4, then some of the pp's books might come in handy.