First, I am SO SORRY you are dealing with this.
So you've tried searching the whole computer for that file name? And nothing? And do I understand correctly that at the least, you have the version you emailed to yourself?
If I were in your shoes, I would phone the geek squad at a big tech store, like Future Shop or whatever. Anyways, I'm not very tech savvy, so I'll just send you lots of luck!!!
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