Though you can search and use some facebook apps like “export contacts” to get all the facebook contacts, these apps are less likely to work. Another way is to use Yahoo Mail to get all the contacts (Google and Facebook are anti so they do not allow any interaction with each other and thus you cannot use the same trick in Gmail). Follow these simple steps:
Log-in to your Yahoo Mail account
Click on Contacts tab
On this page there is an option to import contacts, click on it
Now you can see options to import contacts from Facebook, Gmail, Hotmail and Others
Click on Facebook and allow Facebook to access your information
Thus you got all the Emails of your Facebook contacts
Now go back to Contacts tab and click on Actions drop down button
In there select Export All
Now you have all the contacts in CSV format