In addition to giving users the ability to share their photos and status updates with their friends, Facebook also provides users with a forum to share their contact information and other important details in their individual profiles. You can find out someone's e-mail address by visiting their Facebook profile.
Log in to your Facebook account.
Enter the name of the person whose e-mail address you are seeking into the Search field found in the upper left corner of the next screen. If this person is already on your Facebook friends list, the website should display their name in bold underneath the text box when you begin typing. Click on this name. If this person is not already your friend, type in their full name, press "Enter" and then find the person you are looking for in the search results displayed on the next page.
You should now be looking at the profile page of the person whose e-mail address you want to find. Click on the "About" link underneath the person's picture at the left side of the page. This will display a list of the information that the person has decided to share on Facebook.
Scroll down the list of details and find the heading that says "Contact Information." If the person has chosen to share his or her e-mail address, it will be displayed here. If the email address is not displayed here, it is not possible to acquire their e-mail address from Facebook without just asking them for it.
Some users prevent people who have not been added to their friends list from accessing the information they share on their profile. If after finding a person's profile you see a message telling you that they have chosen to limit the information displayed on their profile,click the "Add Friend" link to request that you be added to their friends list. Once added you will be able to see all of the information on their profile.