The Chasch by Jack Vance, first installment of the Tschai saga, can be downloaded for free from the author's website (registration required). The ebook comes in epub and mobi formats and is DRM-free. This is the description of the novel:
The starship Explorator IV is destroyed after entering orbit around the planet Tschai. Adam Reith's scout ship is en route to the surface when the attack occurs, and is damaged in the explosion; Reith crash-lands and is separated from his ship. He finds a world full of violence, where four non-human races rule: the Chasch, the Dirdir, the Wannek, and the Pnume. Humans are present, but dominated by the other races. In this volume Reith sets out to regain his scout ship, and makes his way to Dadiche, ruled by the Blue Chasch and their human servants. Along the way he finds loyal friends, and challenges social inequities with the same aplomb that he rescues fair maidens- like the lovely Ylin Ylan, Flower of Cath.