Yea, Purdy is a good writer. If you're looking for some common-sense, down to earth instruction Purdy is excellent, although his analysis of openings is a little dated. Most of the books are published by Thinker's Press. I like his Extreme Chess, about the World Championships 1935, 37--Ewe Alekhine and 1972--Fischer Spassky. Most of his newer books (since he is deceased) are compilations of his writings from the Australiasion Chess Review, Check, and Chess World, the copyright being released by his wife, Mrs. Anne Purdy.