How to find a email address on web?

I would like to inform you that email addresses are quite protected and there is no such way to know regarding the telephone number and address associated with it. Yahoo, Rediff are very sincere and protective about the confidentiality of the information. They repeatedly send their mails, telling their customers not to give their accounts related information to anybody.

1. To know the contact information, email ID of any person, you can take assistance of social networking sites and seek about the whereabouts of any person. In such websites like Facebook or Friendfinders keep a lot of information in the membership profiles of the members and from there you may be able to get some of the information about a particular person. You can demand such information by becoming friends with the members and writing to them for phone numbers and other related information.
2. Google is another site for knowing information about any person. Go directly to the search column and type the name of that person. If he/she has details in the NET, you can know immediately.