How do I lookup a caller with only a phone number?

I've called back, googled, looked up all the companies that I've sent resumes to, and used yellowpages.

I got a call this morning which I thought was my alarm, and I pressed a random button and gone was the sound. Only to realise later that it was a call from a landline. This situation calls for a face like this.. -______________-

Job hunting ma. I'm very paranoid at the moment. I called back but the line is always busy. Doesn't that say, I'm an office phone, all over?

EDIT: Wrong number.. -______________-

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Double renovations going on at my neighbours on the left. The drilling, knocking and crumbling..