Audio Editing Software...

Avid Protools is by far the easiest, the best and the most powerful.
Ubiquitousness(?) also an important factor.
Especially now Protools 9 has gone native.

I'm trying to find a trial version I can check out. It's too expensive for me to just shell out the cash. Do you know if they have trial versions for that.

There was a version called Protools Free quite a while back. If you're still running windows 98 or Mac os9 you could be in luck. Any other versions you find will require digidesign or Mbox hardware to run anyway.

I guess you could watch some YouTube tutorials to get a good idea of how it works. The point is though, it's good enough to be used for anything from homegrown VoiceOver booths to Hollywood film scores.

If you want a free trial (and very cheap anyway) alternative you could try Reaper. It's good, buts it's no Protools.

"Audacity" might be worth a look too. Also free. Used to be called "Cool Edit" back in the day.

Here's a handy comparison grid on a respected site:
http://www.synthzone.com/digaudio.htm

I work in the field of speech recognition (where audio editing is rather important). Many of us use Audacity as our go to tool. Audacity is not a trial... it is free (open source.

I recommend you start there before you spend any money on something else.