I'm in the Copper Coronet sewers and I'm stuck at the part where you have to find the four peices to get the sword. I have the hand, the ring, and the staff. Can anyone tell me what and where the last peice is?

kill the bum's pet

'blood of a friend'

what? copper coronet sewers? despite my many times through i have never been to such a place...i haven't found a use for the "slaver" place marked in the slums, and i have a couple of dead ends in the underdark. How would i get there, and where would i find these pieces?

Get Lehtinan to let you into the back rooms by telling him you want to dispose of some coin. Later on free Hendak.

oh...i always kill lehintan cuz then bernard gives you better stuff, and i was wondering who hendak is. Can you get back there if lehintan is dead?

Erm... Well, maybe that's one of the effects of killing Lehtinan, but I'm not entirely sure if that will screw up the rest of the quest or not; as at the moment you save Hendak, he will move to Lehtinan in order to kill him.
And no, I don't think you could get back there when Lehtinan is dead, not without his permission I believe.