The first two are both "Hamasaki Ayumi no Himitsu (Secrets of Ayumi Hamasaki)" by "Ayu Reporting Group." The first publishing of the book (the pink cover on top) is from September 2001. It is 221 pages long. The book was updated twice - once in June 2002 with the black cover above (not sure how many pages long this version was), and again in 2005 - this version had 334 pages and was released with this cover:
As for "Pure Stories," amazon.co.jp has the "look inside!" feature for that book here:
http://www.amazon.co.jp/gp/reader/49...pt#reader-link
173 pages, June 2005.
"Secrets" tends to focus more on her early life & aidoru era, while "Pure Stories" seems to focus more on her emotions during her avex career. Without reading both, I couldn't tell you for sure, but that's what it looks like.