My 2009 book Not the Impossible Faith is now available as an audio book. As I did for Sense and Goodness without God and Why I Am Not a Christian, I voiced the text for Pitchstone Publishing. You can buy NIF now through Audible.com or Amazon.com and also iTunes.
As usual, this is a somewhat “abridged” version, in the sense that it contains none of the chapter endnotes (and thus the sources are not there, nor any of the note anchors in the text itself). So for the visually impaired I have assembled those as a single PDF which you can run through a text-to-speech reader if needed (although you’ll have to guess where the notes refer to in the main text; the PDF only segregates them by chapter): see NIFaudiobookNotes.pdf.
There is also a PDF edition of the whole book for under three dollars [here] or an eBook edition for under six dollars [here] or kindle edition for about the same [here]. A voice-to-text on any of those will presumably include the note anchors as well as the notes, but alas it won’t be a human-voiced main text.