When you find yourself trying to remember a show (or any works) that's on the tip of your tongue but just out of reach, come here - the collective brain of the TVTropes community can probably help. Post all the details you can remember (examples help). If you're looking for a trope, head over to Trope Finder. Have general questions about tropes? Visit Ask The Tropers!
Hey dragonchick, what sort of subgenre of Sci-Fi is this book if you remember? It may be possible I've heard of it before.
Lover of Foo Fighters, Good Books and being different.I think you're talking about The Inferior. I linked below to the Amazon listing, because that's the best picture I can find of the cover you mentioned.
Amazon link: http://www.amazon.com/The-Inferior-Peadar-%C3%93-Guil%C3%ADn/dp/B002XULYGE
It was a purple book with a single arrowhead on the cover, in the Sci-Fi genre. It was about this tribe that lived near a swamp, and they were in conflict with nearby species. The main character stutters and his brother is the leader of the tribe. New species fall from the sky periodically; one day a lady (same species as main character) falls from the sky, speaking in tongues. Main character recovers the lady's translator and they go on a journey, abandoning the tribe, to get the lady back into the sky to her people. In the end, they discover another person from the sky, the main character is forced to kill them, and lady returns back to her people; it's revealed everything is all one big experiment.
No idea what this book's title is, please let me know if you have an idea!