I cannot specifically help from an application standpoint. But two suggestions -- go to a bookstore and get imovie: the missing manual, by David Pogue. That's like an instruction manual (or at least look through it for help).
Also -- check the apple discussion boards and maybe someone there can help, too. It's on the apple site, under "support" and then "discussion," I believe it is.
And good luck. I know you're panicking right now, as I would be, too. See if those options will help you out and get you back on track.