Audio Editing

[magus176]

While I work on LOTR (not going quickly), I'm interested in making, shall we say...amateur music videos. To do so, however, I need to learn how to edit audio to strip it of a soundtrack but leave voices intact. Is there any way to do so? Or say I have an audio file with a terrible "buzz" or ringing noise in the background. Is there any way to get rid of that?
Or at least layer audio (adding more audio tracks into it, like a "mux")? If not, I will simply be quiet.

[setarip]

"Or say I have an audio file with a terrible "buzz" or ringing noise in the background. Is there any way to get rid of that?"

Software such as GoldWave, CoolEdit and their ilk, can eliminate pops, hisses, etc. There are probably also some less full-featured programs floating around that deal ONLY with such audio problems.