I recently changed my email address (through the Profile window). I can now correctly log in with the new address.
However, I still receive emails (updates of new courses) on the old email.
How do I get this fixed?
Your Codecademy profile will have your e-mail listed there, as well. Log in to that profile and change it there. MInd, I’m only suggesting this, not having tried to do it myself. Will take a look and check back.
Update:
Assuming your alias is the same for both accounts,
https://www.codecademy.com/__your_alias__
Then in the pull-down at top right (click your avatar) select My Account.
I only just created the forum account when I found this issue, so it is only related to the main website, not the forums.
I checked the email address in the My Account settings, and it correctly shows the new email address (and that is the same one I use to log in).
But the emails are coming in on the old address 
It may be that the notification database only gets reconciled periodically. It may take a while for the changes to take effect.