I have heard that ALO's receive something that can be presented at an awards banquet--not sure if that is true, but wouldn't that be nice?!?!?
Not all ALOs do this. My DD's ALO came to her senior awards in dress blues and gave a very nice presentation, with the appointment certificate and her first RMO.
You actual notification will be an email to say you have a message on your portal, which will be the official appointment letter, but it is nothing fancy. Check with your ALO ASAP to see if s/he is willing to do the presentation.