If you want to know what your friend’s e-mail is, but he is hiding it from facebook, that you can use this method and get his e-mail. There was no way to view their e-mail address, but I have found one way to do it. Just follow the steps below.
1) Got to this link and make a UK account.
2)Now you need to go to contacts tab when you sign in.
3) Click on Import contacts.
4) Choose facebook.
5) Now a pop up will appear looking like this, if you are not logged in.
6) If you are logged in click ok.
7) Once everything is finished, it will say no contacts are imported, then you will need to press ok it will redirect you to a new page with all your facebook contacts followed with their e-mail.