Ok, so I'am re-reading the series and I feel like i need to know right now who wrote the letter to Rand in Far Madding telling him where the renegades are. Chapter 32 of Winters Heart

 

"I know who you are, and I wish you well, but I also wish you gone from Far Madding. The Dragon Reborn leaves death and destruction where he steps. I know why you are here, too. You killed Rochaid, and Kisman also is dead. Torval and Gedwyn have taken the top floor above a bootmaker named Zeram on Blue Carp Street, just above the Illian Gate. Kill them and go, and leave Far Madding in peace."

 

 

Thanks for the help people

Pretty sure it was Fain attempting to lure Rand into an ambush.  It was Rand dropping into the room with the bodies that alerted Rand what was up and to get ready.

The Encyclopaedia site tells that the note was from Fain.

http://encyclopaedia-wot.org/books/wh/ch32.html