Global Address Lookups on Galaxy SIII
So what I've discovered so far,

Android doesn't have this functionality yet and you'll need to install a 3rd-party app to get this. An app that I found works is 'Swift Contacts'.

What's nice is I am able to type the name of the person right in the 'To:' field and it does a lookup and completes the email address. The only problem is I think this app will stop working after a period of time if you don't pay for it. I haven't found a free alternative for it.