40 total titles free to pre-order for those in Australia, all from Harper Collins, it appears. A few of these are the 12 Days of Christmas stories (and anthology), but the rest appear to be mostly history and short stories, along with one cookbook.
There are actually a very large number of free Harper titles for Australians. I'm working on a full list, but you can start with
this search.
- Halfway to the Grave with Bonus Material: A Night Huntress Novel by Jeaniene Frost
- Happily Never After by Jeaniene Frost
- A Very Vampy Christmas: From Sugarplums and Scandal by Kerrelyn Sparks
- Rose in Bloom: A Novella with Bonus Excerpts by Stephanie Laurens
- Fatal Heat: A Navy SEAL Novella by Lisa Marie Rice
- Royal Weddings: An Original Anthology by Stephanie Laurens, Gaelen Foley and Loretta Chase
- Reckoning: From Unbound by Jeaniene Frost
- A Lady's Wish by Katharine Ashe
- The Amanda Project: Book 2: Revealed: Part 1: Chapters 1-3 by Amanda Valentino and Peter Silsbee
- Diaries of an Urban Panther by Amanda Arista
- Before the Witches: An Original Novella by Karina Cooper
- He Kills Me, He Kills Me Not by Lena Diaz
- Dark Future by Kc Klein
- The Perfect Hero by Victoria Connelly
- The Treats Truck Baking Book by Kim Ima
- 1066: History in an Hour by Kaye Jones
- American Slavery: History in an Hour by Kat Smutz
- Ancient Egypt: History in an Hour by Anthony Holmes
- Henry VIII's Wives: History in an Hour by Julie Wheeler
- Hitler: History in an Hour by Rupert Colley
- Nazi Germany: History in an Hour by Rupert Colley
- The Reformation: History in an Hour by Edward A Gosselin
- World War Two: History in an Hour by Rupert Colley
- Les Très Riches Heures de Mrs Mole by Ronald Searle
- Sawbones: A Novella by Stuart MacBride
- Clues to Christie: The Definitive Guide to Miss Marple, Hercule Poirot and all of Agatha Christie's Mysteries
- Sharpe's Company, Sharpe's Sword, Sharpe's Enemy by Bernard Cornwell
- Frankenstein Special Edition: Prodigal Son and City of Night [ePub edition] by Dean Koontz
- 77 Shadow Street by Dean Koontz
- Brought in Dead (Nick Miller 2) by Jack Higgins
- Sam Bourne Bundle by Sam Bourne
- Sheba by Jack Higgins
- The Great Bazaar and Brayan's Gold by Peter V. Brett
- Michael Stanley Bundle: A Carrion Death & The 2nd Death of Goodluck Tinubu: The Detective Kubu Mysteries with Exclusive Excerpt of Death of the Mantis by Michael Stanley
- JENNY LOPEZ HAS A BAD WEEK by Lindsey Kelk
- Twelve Days of Winter: Crime at Christmas (3) - French Hens by Stuart MacBride
- Twelve Days of Winter: Crime at Christmas (4) - Calling Birds by Stuart MacBride
- Twelve Days of Winter: Crime at Christmas (7) - Swans A Swimming by Stuart MacBride
- Twelve Days of Winter: Crime at Christmas (9) - Ladies Dancing by Stuart MacBride
- Twelve Days of Winter: Crime at Christmas by Stuart MacBride
- Twelve Days of Winter: Crime at Christmas (1) - A Partridge in a Pear Tree by Stuart MacBride
- Twelve Days of Winter: Crime at Christmas (2) - Turtle Doves by Stuart MacBride
- Twelve Days of Winter: Crime at Christmas (5) - Gold Rings by Stuart MacBride
- Twelve Days of Winter: Crime at Christmas (10) - Lords A Leaping by Stuart MacBride
- Twelve Days of Winter: Crime at Christmas (6) - Geese A Laying by Stuart MacBride
- Twelve Days of Winter: Crime at Christmas (8) - Maids A Milking by Stuart MacBride
- Twelve Days of Winter: Crime at Christmas (11) - Pipers Piping by Stuart MacBride
- Twelve Days of Winter: Crime at Christmas (12) - Drummers Drumming by Stuart MacBride
- Warriors Digital Novella by Erin Hunter
- Hunting Kat by Kelley Armstrong
- Trafficked: The Terrifying True Story of a British Girl Forced into the Sex Trade by Sophie Hayes
- Birthdays for the Dead by Stuart MacBride
- The Dice Man by Luke Rhinehart
- Grumpy Old Men: New Year, Same Old Crap by David Quantick
- The Time of My Life by Cecelia Ahern
- Pitch Dark: Dark Days of Fall Sampler: Supernaturally; Fateful; Cold Kiss; A Beautiful Dark; and Eve by Amy Garvey, Claudia Gray, Anna Carey and Kiersten White
- Bleak Water by Danuta Reah
- Wishing for Snow by Minrose Gwin
- PitchDark Presents the Dark Days of Supernatural Paranormal Romance Sampler by Various
- The Loving Daylights (B.L.I.S.S.) by Lynsay Sands
- Beyond Moralism by John Shelby Spong
- American Hunger by Richard Wright
- The Easter Moment by John Shelby Spong
- Parting Gifts by Lorraine Heath
- Sweet Lullaby by Lorraine Heath
- Texas Destiny (Leigh Family) by Lorraine Heath
- Texas Glory (Leigh Family) by Lorraine Heath
- Every Year: Short Stories by Cecelia Ahern
- A Taste of Irrationality: Sample chapters from Predictably Irrational and Upside of Irrationality by Dan Ariely
- A Girl's Guide to Vampires (Dark Ones) by Katie MacAlister
- Stopping Time (Wicked Lovely) by Melissa Marr
- Stepping Out Within by Robert W. Olsen
- After Dark (Dark Realm) by Delilah Devlin
- Another Door by Jess Michaels
- Fallen Angel by Jess Michaels
- It's in His Kiss: The Epilogue II (Bridgerton Family) by Julia Quinn
- Lady Amelia's Secret Lover by Victoria Alexander
- The Lover Hunt by Jess Michaels
- Magic and Mayhem by Sylvia Day and Cathryn Fox
- Parlor Games by Leda Swann
- Polly's Game by Leda Swann
- Que Se Yo del Universo (Don't Know Much About...) (Spanish Edition) by Kenneth C. Davis
- Unrequited by Kimberly Dean
- Victim of Deception by Lynn Lafleur
- Agent Provocateur by Liz Maverick
- If the Holy Spirit Comes for You by Barb Johnson
- Issue Is by Barb Johnson
- Killer Heart by Barb Johnson
- Titty Baby by Barb Johnson
- What Was Left by Barb Johnson
- Allegory of a Cave by Holly Goddard Jones
- Good Girl by Holly Goddard Jones
- Life Expectancy by Holly Goddard Jones
- An Offer From a Gentleman: The Epilogue II (Bridgerton Family) by Julia Quinn
- Parts by Holly Goddard Jones
- Proof of God by Holly Goddard Jones
- Theory of Realty by Holly Goddard Jones
- To Sir Phillip, With Love: The Epilogue II (Bridgerton Family) by Julia Quinn
- Mistress of Paradise by Alexandra Benedict
- The City of Windy Trees (P.S.) by Simon Van Booy
- The Coming and Going of Strangers (P.S.) by Simon Van Booy
- Love Begins in Winter (P.S.) by Simon Van Booy
- The Missing Statues (P.S.) by Simon Van Booy
- Imponderables (Imponderables®) by David Feldman and Kas Schwan
- Reunion by Lynn Lafleur
- Romancing Mister Bridgerton: The Epilogue II (Bridgerton Family) by Julia Quinn
- These Wicked Games by Sherry Ledington, Courtney Milan, Lacey Kumanchik and Eve Ortega
- The Viscount Who Loved Me: The Epilogue II (Bridgerton Family) by Julia Quinn
- When He Was Wicked: The Epilogue II (Bridgerton Family) by Julia Quinn
- Escape the Diet Trap by Dr John Briffa
- The Hunting of Man: A History of the Sniper by Andy Dougan
- Collins Know Your World Series - China
- Collins Know Your World Series - Egypt
- Collins Know Your World Series - Germany
- Collins Know Your World Series - India
- Collins Know Your World Series - Japan
- Collins Know Your World Series - Nigeria
- Collins Know Your World Series - UK