Open Road is having a Christmas Mysteries sale. I think I saw somewhere that it was good through 12/31, but now I can't find where I think I saw it, so that's a bit uncertain.
Link is here:
http://www.openroadmedia.com/christmasmysteries
This provides access to various retailers - when you click on the little red "Buy the Ebook" button under each book, you get a pull-down to choose your retailer. Or, you can just search directly for the titles on your preferred retailer's website yourself.
The Open Road sale page doesn't list any prices, but I spot checked a few in Kobo Canada (since PERKOPOLIS still works on Open Road titles there for 40% off) and the books seem to range from $1.99 to $3.99 there.
The books in the sale are:
Charlotte MacLeod:
Rest You Merry,
Murder Goes Mumming,
The Convivial Codfish
Nero Blanc:
Crossworder's Delight,
Wrapped Up in Crosswords,
Crossworder's Holiday,
Crossworder's Gift
Jane Haddam:
Not a Creature Was Stirring,
A Stillness in Bethlehem
William Bernhardt:
The Midnight before Christmas
Jane Langton:
The Shortest Day,
The Memorial Hall Murder
Lawrence Sanders:
The Fourth Deadly Sin
Frederick Forsyth:
The Shepherd
Ellery Queen:
The Egyptian Cross Mystery
Gillian White:
The Sleeper
Karl Harter:
Winter of Frozen Dreams
John Harvey:
Cold Light
Michael Allegretto:
Night of Reunion
Mignon G. Eberhardt:
Postmark Murder
Loren D. Estleman:
The Glass Highway
J. Robert Janes:
Salamander
Andrew Klavan:
The Scarred Man
Stuart Palmer:
Omit Flowers
William L DeAndrea:
Killed on the Ice