If you're interested in this space, my recommendation is to use Wink. Spock is still in closed beta, and PeekYou's current beta is unimpressive. Despite the company's claim of 50 million people in the database, there are many duplicates (over 700 entries for George Bush, each with a few links--and typing George W. Bush doesn't work to narrow the results). And there's no good way to tell who's who in a list of similar names. Which of the seven Stephen Hawkings returned is the physicist? None of them, as it turns out (the one link tagged with a U.K. location goes to a fake MySpace page).
In searching for my own name (vanity, thy name is Blogger), I found links to an out-of-date personal blog, MySpace, and Ryze (a social network I haven't used since 2002), but nothing current. No Webware, LinkedIn, Facebook, Twitter, etc.
PeekYou claims similar features to Spock and Wink: Users can "claim" their own profile and even make themselves unlisted. But my advice is to not get sucked into this product. It's barely ready for public access, and certainly not worth the time if you've got an important search to do.
We're also checking out Gleamd, an aggregator on comments about people, which is still in private beta.