Samak Sunthonwet: nayokratthamontri khon thi 25 (Samak Sunthonwet: the 25th Prime Minister) (2008) by Thanomsak Chirayusawat (ISBN: 9789747814514). This modest volume provides useful coverage of Samak’s life, up to his current success. It includes some interesting detail on his early life, his professional and private life, the beginning and progress of his political career, and various achievements and honours. It has some good good coverage of his personal hobbies and talents!
New Mandala readers may be interested to read the back cover blurbs by former-PM Thaksin and others.