By clicking generated campaign link (or scanning QR code) Facebook users can like your page and/or add viral message with your link to their timeline. To motivate users you can reward them with coupon codes or one time or unlimited download of your book or audio file. Coupons are generated, managed and invalidated in your likefull.net account.
Emails are also collected and likefull.net has simple email campaign service built in. You can email users collected by campaigns ( each only receives one email even if he is in different campaigns ) or exclude certain campaigns. For email delivery Mandrill from Mail Chimp is used - a world class email delivery system so you can be confident they arrive to inbox folder and are not eaten by spam monsters.