I think there are only 3 valyrian sword in the show at the moment. Johns, Tommens ( was Joffrey's gift from his father, guessing it got passed down? ), and Brienne of Tarth's ( Was Jamie's until he gave it to Brienne ).. There might be more else where, but pretty sure those are the only ones in the story line.
EDIT: Oh shit there was a dagger wasn't there? Little finger has it?!