How to locate config.yml in rails app with a gem

I am writing a ruby gem for rails applications and I would like to load information from a yml file located in /config of each app (something that a lot of gems do) so everytime the user instantiate one of my classes in the controllers or any other Ruby file it loads the information there. Ideally I would also like to create a sample file for the user once he runs bundle install in the project.

Thank you very much