If you really are editing video in the wild, one of the first casualties will be your audio monitoring. Sure, you can monitor with headphones, and that will give you a good idea of the basic blend and quality of sound. Unfortunately, headphones don't sound like speakers and most of your viewers will hear the finished product on speakers. If you can catch a transport off the island, take your edited video along for a test on several playback systems. Try everything from a home theater to a simple mono television. If the mix holds up here, great. If not, make notes about where it was hard to hear dialog, where music was too loud or soft and how the sound effects fit in the mix. Once you're back in your desert paradise, make adjustments based on these notes. Your newly balanced soundtrack should playback nicely on virtually every system. If anyone ever gets to see it, that is.
For whatever reason, it may be difficult or impractical to edit audio in your video software. If that's the case, it's easy to edit audio in a dedicated package like Adobe's Audition or Sony's Sound Forge. You can export audio from individual clips or your entire project, treat it as needed in the audio app and then drop it back into your video project. In an audio-specific program, adjustments are easier with a greater degree of control and you'll have every bell and whistle known to the free world at your disposal.
Digital Audio Sampling
Audio For Video: How To Mix Stereo
Introduction to Digital Video Editing: The Guide to Getting Started With Computer Video (DVD)
Sound Success (DVD)
Advanced Editing -- Guide to Advanced Computer Video Editing (DVD)
Audio Compression
Composition 201
Fix It in Post
Video Glossary of Terms
Radio and Dialog Editing