Song: Epitaph
Anime Series: .hack//Liminality
Composer: Kajiura Yuki
Instruments: Primarily the Piano, Violin, Cello parts. Including the Bells and Shakers parts would be great, if possible.

I've been looking all over for this piece, since I want to play this for a video game/anime chamber ensemble that I'm part of. If anyone could help provide the sheet music for this piece for Piano, Violin, and Cello, that would be greatly appreciated. Thanks.

This person looks like they have a midi that you could adapt: http://www.youtube.com/watch?v=aeXbV_vzBq8

The youtuber also included a link to the midi file! If I'm correct, there are programs or online services that can convert multi instrumental midis to sheet for you.
Here's after a quick google search, but I don't know how well. It would be a good start as I think it'll decide a key for you. http://www.8notes.com/midi_sheet_music/