There are lots of places to lookup information that you might not think of right off the top of your head.
For looking up people in the United States, there is…
The People Finder Lookup at MelissaData. You don't get a complete phone book listing (but you know where that is, right?), but the database is still interesting because it searches multiple sources, and will tell you if a listing exists, and the age, town, and possible relatives and aliases of the person. And for more detailed information, you can always elect to purchase a detailed report.
Prison contact and inmate lookup information. If someone you know is, or might be, in jail, this is the place to begin looking. Unless, of course, they're in a federal prison, in which case check the Bureau of Prisons' Inmate Locator.
And if your prisoner needs a bit of assistance, Martindale's the place to look for lawyers.
Tax Refund Finder is worth a look if you think (or merely hope) that the IRS owes you or someone you know some money.
Jigsaw is a site where you can “Buy, Sell and Trade Business Contacts”. It's an odd and pretty interesting information bartering system, and probably pretty annoying for all those private office execs whose phone numbers are being outed. And, too, it takes a while to get the hang of it. But if you're looking for business contacts, take advantage of their Free Trial and give 'em a whirl.
Birthday lookups. Yep, believe it or not, you can find an awful lot of birthdays here (but be sure to hit the SEARCH button…hitting Enter won't work). My birthdate isn't in the records, but both my parents are…conveniently for me, as I'm always forgetting just which birthday is coming up when.
Politicians. Federal, state and local government officials are all here, in all their moderately effectual glory.
There are plenty of doctor search tools, but I'm fond of the large database at Dr-411.
I'm still getting used to Zabasearch, which bills itself as a powerful people finder. I'm not really recommending it…just letting y'all know it's there.
So…let's see you find pafalafaga David Sarokin!