In adjective order, "opinions" come before "descriptions".
So, in the sentence
It was a normal strange book
Sounds okay to me, it "normal" would be your opinion and strange a description of it.
Of course, the sentence could be made into "It was a normal and strange book" or "It was a normal and yet a strange book", but then the emphasis on "your opinion" vs "description" would be lost.
Both would be just equal characteristics of the book.
Another way to see this one, is that "normal" is the most innate, fundamental quality of the book.http://linguapress.com/grammar/adjective-order.htm
As for the second sentence, I would hazard the guess that "It was a strangely normal book" would be a better wording. Sounds like the book was normal, even if one wouldn´t expect it to be.
To have the same effect as the previous example, one would say "it was an strange, and/but at the same time, normal book."
Others may disagree, or polish the answer more.