Best commentary on Jonah is by Youngblood, called God's Scandalous Mercy. Also, pick up Daniel Timmer's volume on Jonah called A Gracious and Compassionate God. Martin is good, in the Geneva series, and so is Rosemary Dixon's volume in the Bible Speaks Today series. Rick Phillips wrote Jonah and Micah for the Reformed Expository Commentary series, and that is outstanding. John Mackay's volume on Jonah-Zephaniah is briefer, but always worth consulting. Estelle's volume is good, if you can stand having to work through pages where the footnotes take up more space than the regular material.