The Elvenbane (Halfblood Chronicles, Bk. 1)

The Elvenbane - Andre Norton, Mercedes Lackey The first of the series by Andre Norton and Mercedes Lackey, an interesting read about a human world where elves and dragons have invaded, dragons almost invisibly and elves as human slave-masters. Half Elves possess possible power to take down the evil masters, so they're killed, one survives and is found by Dragons.