
A nice reference library of vintage Leica brochures and manuals can be found here. See also my own collection of vintage Leica camera advertisement posters and banners:

Frankencamera has published the detailed steps on how to convert an old Leica M3 into a digital camera. One of the options is to use a Sony NEX-5 sensor (APS-C), the second choice is a Sony a7 sensor (full-frame). Frankencamera also provides/sells all the necessary steps and 3D designs you will need to complete this project.

Leica Camera has announced an online series of complimentary educational talks to help bring the community together over our shared love of photography and help provide the tools you may need to stay active with your cameras and continue to build your skills, while safely social distancing during this challenging time.