You have to create a Profile Plugin for this task,
and use the onUserAfterSave
for the folder creation section.
the basic profile plugin documentation can be found here.
Another option is just edit the core file, but its not recommended bcoz due to Joomla update it may lost.
If you plan to edit core file just check your model file inside components/com_users/models/registration.php
and task register()
in this function a send mail code is there just add your custom codes before that.
Hope its helps..