Two programs that I would suggest are:
Expstudio Audio Editor - (http://download.cnet.com/Expstudio-Audio-Editor-Free/3000-2170_4-10444774.html?tag=mncol)
Audacity - (http://audacity.sourceforge.net/)
Audacity might be a little overkill if you just want to use it for audio leveling. Unfortunately, as far as I know, both programs do not support "batch" processing, but can run in multiple instances (or more than one file open at the same time); you'll just have to apply leveling one by one to each track.
Hope that helps.
I have a couple thousand songs from a couple different sources and they have different volumes. I am looking for a free program that I can put all my songs into and it will level out the volume. I am not looking for something like iTunes "sound check" I want something that will save the songs.