Hey nsferg,
Congratulations on your new iPhone 5s!
The following article may help you in setting up Touch ID:
iPhone 5s: Using Touch ID
http://support.apple.com/kb/HT5883
Setting up Touch ID
You can set up Touch ID in iOS setup assistant or by tapping Settings > General > Passcode & Fingerprint > Fingerprints. To configure Touch ID, you must first set up a passcode. Touch ID is designed to minimize the input of your passcode, but your passcode will be needed for additional security validation, such as enrolling new fingerprints.
Enjoy your new phone,
Matt M.