Macmillan's eDeals page has
Earth Unaware, the first book in the First Formic War series by Orson Scott Card and Aaron Johnston for $2.99 at US / Canada / New Zealand retailers. (Not Australia though, probably because Hachette have exclusive rights there.)
(As seems to be the way with these Macmillan specials now, the New Zealand price ranges from $US2.99 to $NZ2.99, with the cheapest being
Apple at $NZ2.99.)