I wish I could help you, but to be honest, it is impossible to find someone just from name and prefecture.
To get the phone number from a yellow book, you at least need full name of the head of the family (or the person who made the contract with the phone company) and full address. And home phone number is shown in the phone directory book only the person agreed. I, for example, asked the phone company not to show mine, because I do not want to be bothered by sales people who pick up phone numbers from it.
The population of Shizuoka is 3.8 million, and number of households in Shizuoka is 1.35 million, you see how difficult to find a person just with her name...
As she was a student in Canada, I wonder if the school she used to be studying in Canada could help. I don't think the school would give you any private information (such as address or phone number), but maybe you can get from which school in Shizuoka she was from... It might be possible to track her down by making inquiry with the school in Shizuoka, though I cannot guarantee.
I wish you good luck.
