Type the author's last name followed by the author's first name, and then a period, as follows:
Happy, John.
Type the online book's title in italics, followed by a period:
Happy, John. (italics)The Happy Writing Book (italics).
Type the place of publication, if listed, followed by the copyright holder and the date:
Happy, John. (italics)The Happy Writing Book (italics). Happy University: John Happy, 2010.
Type the name of the site you acquired the online book from, followed by a period, and then type "Web" followed by a period, and then type the date.
Happy, John. (italics)The Happy Writing Book (italics). Big Writing Publishing: John Happy, 2010. The Big Writing Blog. Web. 23 Sept. 2011.