Gail Bowen has three bundles available in the US and Canada, at least:
The Early Investigations of Joanne Kilbourn
http://store.kobobooks.com/en-US/ebo...oanne-kilbourn
The Further Investigations of Joanne Kilbourn
http://store.kobobooks.com/en-US/ebo...oanne-kilbourn
The Gail Bowen Ebook Bundle
http://store.kobobooks.com/en-US/ebo...n-ebook-bundle
The first two feature (not surprising) Joanne Kilbourn as the sleuth, and the third one features talk-show radio host Charlie D.
I bought all three a while back and can't remember if they were couponable. The first two weren't, I think, and the last one was, but that's just how I remember it, and it may have changed since then, or be different in various countries.