Freedom's Choice by Anne McCaffrey - USED

When Kris Bjornson and her fellow slaves were dumped on an uninhabited planet by their Catteni masters, there was no guarantee they would live through the first day. Without the help of Zainal, a renegade Catteni exiled by his own people, they might all have been food for the terrifying predators of the new world. But the colonists have learned to survive, and now they have a busy little civilization growing in the caves and fields of the planet they named Botany. Automated farming machines left behind by the true owners of this world have provided metal and parts for inventions that make their lives easier - and also have made them wonder about the identity of these "farmers." Botany's owners seem to keep watch on their world with automatic scanners; surely they will come in person sometime, if only to see who is trespassing on their land. Maybe they will help Earth against the Catteni and Eosi, who have enslaved many worlds.