I guess you could use Audicity but that's sort of hard to use if it's your first time trying it out.

You can find guides here http://www.edhsonline.org/other/audacity/ here http://beginwithsoftware.com/videogu...ity-guide.html and here http://podcasting.about.com/od/podca...inaudacity.htm

I'm not sure if that helped, but good luck finding something you like.