How will they know OP address?
I know he said he was joking but in general. A google search on the email and see what it brings up as well as variations of the first part of the email.
Pop the email into social media and if linked to an account it can pop up.
Once you have social media you can figure out the general location of where they live, work, friends, maybe even a DOB and phone number.
Do an online phonebook search for the social media name
= address.
It's not as hard as you would think to track someone down. A few simple steps can really protect you online.