| I didn't tell them any of these things. In the middle of the night
| they knew. Scary, huh?
|
| Google is not the only one who knows all about you.
|

Google knows what you're doing. I think the
tests you describe are using services like
LexisNexis. That is, companies pay for access
to databases where they can look things up.
(Ever notice how people search pages often
have an option to pay for more info?) Those
databases are owned by companies that just
collect and resell data of all kinds.

I remember reading, some years ago, that when
one calls a car dealer they know how to sell to
you before a salesman gets on the phone: income,
car buying history, etc.

So the test you saw was from a combination of
sources, probably mostly public records.