Find a serial number using Find My Phone app?

My Macbook Air was stolen yesterday and I can't find the original purchase info with my serial number and it's not saved in my apple id records for some reason. It's also not listed under my applesupport profile with the rest of my devices and the support website says, "You can also find a list of serial numbers associated with your Apple ID and get information about using Find My iPhone for iPhone, iPad, iPod touch, or Mac." but I can't find information anywhere on how to do this.

My find my iPhone app is showing the laptop both in the app and online at icloud.com/find, and it is set to lock and erase when connected to wifi, but in the meantime, I want to report my serial number as stolen. Help!