Some mystery & sf which I'll add the extra provenance info to and edit into the main posts later:
Ace & Tor-published Stephen Ames Berry still has his printed milSF space opera novel free from Read an E-Book Week and has now added the sequels @ $2.99
via Smashwords:
The Biofab War
Melanie Jackson wrote historical romances for Dorchester/Leisure. She offers those and some comedic-looking cozy mysteries for $0.99-$3.99
via Smashwords and offers a short story set in one of the cozy series free (and her other series apparently is set in Canada and has Mounties in it, so I'll be downloading samples and waiting for Smashwords sale):
The Sham (A Chloe Boston Mystery Book 14)
More romances:
Sharon Ihle, whom I forget who's published her, but I know people have said she's a favourite, has her historical western romances @ $2.99-$3.99
at various outlets including couponable/loyalty rewards ones like Kobo and Diesel. A 1995 Harper/Monogram historical western is free @ iTunes:
The Bride Wore Spurs
St. Martin's published Wendy Lindstrom has historical romances @ $3.99-$4.49
via Smashwords and offers a Civil War-set one free:
Shades of Honor
ETA: Andrea Parnell (historical & gothic historical romances @ 2.99
via Smashwords) offers her 1st-in-series 1995 Signet-published gothic historical novella:
Dark Prelude