I've added a new downloads section to the Ghibli Blog - Download These Fan Translations. My big project today has been to organize the large number of Miyazaki comics in my collection. I've found and downloaded these scans and fan translations over the years, some by our reliable friends at BakaBT, and others from websites that are no longer alive.
I'm also trying to reach the manga teams who are working on "scanlating" Miyazaki's 1999 comic, Otto Carius - Tigers Covered in Mud. This watercolor manga appeared in Model Grafx magazine in Japan, and five of the six episodes are finished. Only the final installment remains to be completed; thankfully, a 1999 script translation is available online.
I'd like to provide links to all of these comics, for the sake of preserving history. There are a number of sources, but it's still very scattershot, and we need to organize. In a perfect world, yes, there would be a giant book called, "Hayao Miyazaki Comics" that we could buy, which would contain all the short-form comics in the artist's career. Until then, we fans will have to organize the best we can.
If you only know Miyazaki from his directorial films at Studio Ghibli, you've only been exposed to one segment of his work. Remember that he originally wanted to be a manga artist.