How to fix bad audio quality from video

[chauhanneel]

I use the video mode on a digital camera and the audio quality is poor. I am planning to put videos on YouTube and plan to get popular.
I got a sample MP3 file of the audio quality of my camera which got ripped from the QuickTime video file ( http://www.megaupload.com/?d=YYKSH5ZN )
I can fix the video quality and make it look professional, but the audio is not as good.

I need free software to fix audio quality since I don't have a lot of money.
Any software to help?

[patio]

Audacity is Free and may clean it up a bit...
But keep in mind if the original is poor quality it won't get much better...

[rthompson80819]

But keep in mind if the original is poor quality it won't get much better...

People watch shows like CSI:where ever and get an unreasonable idea of how easy it is to clean up video and audio.  It can be done to a small degree but it also takes expensive software and hardware.

[chauhanneel]

Audacity is Free and may clean it up a bit...
But keep in mind if the original is poor quality it won't get much better...

I think I need to use an external microphone and then put the fixed audio with the video in a video editor.