Searching persons behind the anonymous AOL searchers
The most effective way is to ask from searcher itself.
NYT reporters Michael Barbaro and Tom Zeller Jr. done it.
The article A Face Is Exposed for AOL Searcher No. 4417749 is worth of reading.
From the article:
No. 4417749 conducted hundreds of searches over a three-month period on topics ranging from “numb fingers” to “60 single men” to “dog that urinates on everything.”
This is an interesting part:
At first glace, it might appear that Ms. Arnold fears she is suffering from a wide range of ailments. Her search history includes “hand tremors,” “nicotine effects on the body,” “dry mouth” and “bipolar.” But in an interview, Ms. Arnold said she routinely researched medical conditions for her friends to assuage their anxieties.
This research is related to big mistake of AOL.