1. The Assassin's Cloak: An Anthology of the World's Greatest Diarist, Edited by Irene and Alan Taylor (2000). Organized for every day of the year from a rich set of sources--Pepys to Andy Warhol. Bought new.
2. A Book of One's Own: People and Their Diaries, Thomas Mallon (1984). Chroniclers, travelers, confessors, and prisoners have all kept journals and for different reasons. This anthology samples some of each. Bought used, can't remember where.
3. Diary of Samuel Pepys (Modern Library). The first great diarist. Lord of the English Admiralty. Lived thorough the Great Fire of London. Hardback from the Modern Library series. Bought used, can't remember where.