First, you need to set things up in your Amazon account. Here's a link the development team has used which worked well for them:
http://www.bypasspublisher.com/help/amazonses.htm
In arpReach, you then just need to add a new email system in Setup / Email Systems and add the SMTP credentials from your Amazon SES account. You're then good to go.
Here are some things you need to do in order complete the process:
http://support.arpreach.com/support/solutions/articles/74761-setting-up-amazon-ses
