I just got back from practicing and one of my friends (who also plays french horn) brought this sheet music he bought off the internet. It is for a French Horn trio and two of my friends and I played it for our warmup. They have a sample of it here http://www.musicnotes.com/sheetmusic/mtd.asp?ppn=mn0033628 . Just download the thing it tells you to. It will take like a second then you can listen to like 25 measures of the song. It is so cool. It`s called Hans Leo Hassler (O Sing Unto the Lord).