http://www.familyhandyman.com/DIY-Projects/Electrical/Electrical-Repair/fix-underground-wiring
1. It seems that most home insurance policy doesn't cover underground power line. Sorry I was wrong in my previous post.
2. Find a qualified electrician with a line locator. The machine costs >$1000. Maybe some place has it for rent. Once he locates where the power line is cut, mark it.
4. Hire some cheap labor to dig. Shouldn't cost that much.
5. Install the splice kit mentioned in the article to re-connect the cut cable.
I guess I would pay $200 total for everything. Note: I'm always a cheapskate.