This book is really disappointing: very poor spelling and grammar from the author throughout! I don't suppose the Aussies can be blamed for that - as far as I understand they too use apostrophes when a letter has been omitted, such as in "it's" meaning "it is"... Also the examples given for expressions sometimes doesn't tie in or use a completely different expression with the entry they come under.
Great! As an Aussie, I needed to ease my English fiancee into our trip back to the motherland. He loved it. Funny, not necessarily to be used as an example of everything Aussies say, but entertaining nonetheless!