IPython configuration files

The IPython config files are located in your IPython profile (in this example, the default profile) directory (depending on your installation, it can be at ~/.ipython/profile_default/ or ~/.config/ipython/profile_default/, ...). I'm talking about these files:

ipython_config.py
ipython_qtconsole_config.py (if you use the qtconsole)
ipython_notebook_config.py (if you use notebooks)

If you don't see them in that directory, you can create them by recreating the profile (still the default profile):

ipython profile create

You should now see and edit the config files.