LoL FSB Extract
This tool is meant to be passed a FSB file extracted from the League of Legends installation folder. You can use a tool such as The Dargon Project to extract the RAF files from league.
It is not meant to be robust nor meant to be any type of professional piece of software. It just needs to get the job done.
The tool can be downloaded here: lolfsbextract_v1.0.zip
You may want to consult the Sound File Quirks page if your sound files do not sound correct.
You can find the source here: lolfsbextract_v1.0_source.zip
I will be providing some additional documentation here soon, likely tomorrow, 7/1/13. The source has pretty good comments in the mean time.