This traditional Latin textbook, dating from the very early 20th Century, was produced in audio in November 2009. Many students still enjoy using it, and it is popular with people studying Latin at home. My view is that it is useful to use a variety of textbooks; not every author explains every point the same way. Also, reading or listening to a variety of explanations of the same points is good, and increases the chance of learning the material thoroughly. D'Ooge uses more formal grammatical terminology than either Underwood or Adler. His method is known as 'grammar-translation'. This audio course adds a third dimension to his textbook, turning it into a comprehensible input source as well. D'Ooge's textbook also comes with a mini Latin reader with a graded selection of prose in basic Latin. The pdf that the audio was produced from is provided for your convenience.
D'Ooge 'Latin for Beginners'
13 hours 11 minutes of audio
More information about Latinum can be found at Latium Redivivum , including lists of the material graded by ability level.