For Simon Vance fans, and genealogy buffs, one of today's Kindle Daily Deal may appeal.
All three books in the Jefferson Tayte Genealogical Mystery series for $1.99 each - these feature said Mr. Tayte, a genealogist, doing genealogical detective work, solving genealogical mysteries and having a thrilling time doing so (something like that).
Each of the books is paired with it's Audible edition and are $0.99 once you have the Kindle edition, thanks to Whispersync For Voice.
Caveat: Only the second two show up in Amazon as WFV but I already had the first one - from it's original publisher, this author has since been picked up by Thomas & Mercer - and it was matched, for me; it may be that once you buy the Kindle edition of book #1 that Audible will show it as matched and discounted, but do your own due diligence on that first one.
http://www.audible.com/pd/Mysteries-...ook/B00IK16RX0
http://www.audible.com/pd/Mysteries-...ook/B00IK1BSN4
http://www.audible.com/pd/Mysteries-...ok/B00IK0Y9WW/