Pull Emails from Comments

I have a post about a giveaway of mine and I told the users if they wanted to join in the giveaway contest, to write a comment down, along with their email address in the box provided. How would I pull out all of the emails from the box ( there are over 150+ submissions so doing one by one would do me no good) in that one specific thread?

I need to compile the emails into an excel spreadsheet and do some randomization to see who will win the 5 things I am giving away.

Thank you.