How do you get the Ring of Hircine
There is a prisoner in Falkreath called Sinding who did a bad thing. You discover this by talking to a grieving father, although the Elder Scroll Wiki says you can simply visit the prisioner.
Ill Met by Moonlight
Go to the graveyard at falkreach and talk to the man.
He will tell you about his daughter. Then go to the jail and talk to the guy in there and he tell you he is a werewolf. He will ask you to help him get a curse of a ring by killing a white stag, which turns out to be Hircine. Hircine will tell you to kill Sindling (the guy in the jail) but if you go there you can choose to not kill him and get the ring by killing all the hunters, or you can get his hide armor by killing him.