I am pretty unfamiliar with the IGI process. I have searched the films and have gotten a lot of information.

I am pretty unfamiliar with the IGI process. I have searched the films and have gotten a lot of information. My question is do I need to write to the churches to get copies of the original or if I go to a library with the IGI information will I be able to order films that have a copy of the original documents or will the library have more information available?

Thanks in advance for an explanation.