OS X V10.6 Snow Leopard :: How To Move Certain Files To Certain Folders

I am trying to speed up Re-Labeling all my metadata for every song in my library. Basically I need to create a workflow first, but I am having some troubles on how I should be doing it in Automater.

Example filename: "forrestaveryderty_driftinonby_flapjack.m4a" find all filenames that start with the same word before the First underscore (_) create a folder with that same word 

copy files with the same word (BEFORE THE FIRST UNDERSCORE) to their corresponding folder name I then can use Media Rage to select the certain folder and and change the artist name all at once. and I would like it to do that with every file at one time. 

again... 

1: Find files with the same name before the first "underscore"

2: Create a a folder for every different name found (before the first underscore)

3: Copy found files (with same name before the first underscore) to the folder with the same name

Info:
MacBook Pro, Mac OS X (10.6.8)