Your options will be quite limited if you don't wish to pay, as far as I know Adobe Premiere Elements 4 costs about £70 and that includes all you need for editing. If you want to try free, have a look at the thread I started in Forum Announcements called Free Stuff and see if there is anything in there that might be of benefit to you. Yes, you could mix all your audio in Audacity, but what if you want to line particular sounds up with scenes in your video, splitting the audio and video won't give you the control you need when it comes to lining everything up.

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