In this book you will find descriptions and answers to questions that are related to the various I-iter websites.
Where do I localize the messages for "Create Contents"?
Under admin/content/types (example for nap.i-iter: http://nap.i-iter.org/admin/content/types ).
Where do I localize the messages of the Weather application?
These messages are to be found within the "localize" section. Whenever the strings come up using the t() function.