Well its not free but I used to use two back when I was shooting and editing. Both Sound Soap and Sound Forge. Im not sure if Sound Forge was rolled into Vegas or its still a stand alone. But it was pretty good and intuitive back in the day. I take that back, I dont think Sound Soap was an editor, rather a cleaner. back then I was restoring a lot of old LPs.
I think Audacity is what you want but the cheaper versions of Sound Forge are only $25 to $50. I doubt anything free would have the plug ins sound forge has.