Hmm...depends how many you have..but a simple way is to log into a working account....then just post the email of the ones you want to check in the search box...if it comes up with a profile pic then that account is still alive...bit slow and laborious but it can be done
http://www.blackhatworld.com/blackhat-seo/member-downloads/280637-get-facebook-email-lookup-2-0-a.html
this one works REALLY good!!myadtoolz, look it up.