The authors have collected over 135 million birth dates and made them freely available on the Internet. The information comes from everything from driver's records to the warranty and registration cards you send back in when you buy something. When this site went up it was swamped. It was almost as bad as the LDS site. They still have trouble keeping up in high traffic times of the day.
Early morning is the best time to do lookups.
Of course the easiest place, if you have a listed telephone number, is in the local phone book. There are many locators on the Internet that contain phone numbers and give addresses. They can just look up your home in the tax appraisal records on the Internet. If I see you on the street, however, I can follow you home and look up your name in the tax appraisal record of your address on the Internet. If you are in a car, I'll just use the automobile license plate lists that are searchable on the Internet.