stolen iphone?

" can you remotely erase the data that's on it before calling the AT&T to deactivate it?"

If you set up find my iphone on the iphone, then yes.

" I have the password protection on my phone set to if you try the password 10 times, it'll erase all the data on your phone. but if you know how to hack into it, than that does no good."

It is very unlikely that the thief would take the time and effort to hack it when they can restore it and use it as their own.

"

Protect your privacy
with Remote Wipe.

Addresses, phone numbers, email, photos. Your iPhone contains important and personal information — information you probably don’t want in the hands of a stranger. So if you lose your iPhone and displaying a message on it hasn’t resulted in its safe return, you can initiate a remote wipe to restore it to its factory settings. When you eventually find your iPhone, you can restore the data using your most recent backup from iCloudor iTunes."

http://www.apple.com/iphone/built-in-apps/find-my-iphone.html

um..... www.icloud.com

You're welcome.

Remember, no forehead slapping allowed here!