On the backend of your event, the first section is named 'Attendees.' On this tab, you will see the option to view your orders and the emails collected. Orders will show you ticket sales, store purchases and donations.
Hit the Download button next to the Emails Collected label to download a CSV of all the attendees and the information that was collected from them.
For more information on email collection, read the article, 'Choosing and Inputting Event Details.'