Various tools for writers operated by the ReAnimus Press crew:

In Search of Wonder, by Damon Knight
Of Worlds Beyond, by Lloyd Arthur Eshbach, ed.

General:

Specific to Smashwords:

Having Relationships With Characters on the Road to Great Fiction, by Andrew Burt
How To Improve Your Speculative Fiction Openings, by Robert Qualkinbush
More Issues at Hand, by James Blish (as William Atheling, Jr.)Galaxy Magazine: The Dark and the Light Years, by David L. RosheimThe Science Fiction Novel, by Basil Davenport, Robert A. Heinlein, C. M. Kornbluth, Alfred Bester, and Robert BlochThe Craft of Writing Science Fiction that Sells, by Ben BovaStaying Alive - A WriterSF in Dimension, by Alexei and Cory PanshinThe Issue at Hand, by James Blish (as William Atheling, Jr.)Space Travel - A Science Fiction WriterHeinlein in Dimension, by Alexei PanshinFootprints on Sand, by L. Sprague de Camp and Catherine Crook de CampHeinleinAnthopology 101: Reflections, Inspections and Dissections of SF Anthologies, by Bud Webster