Artbooks or behind the scenes notes from games and anime music production

I know this is a long shot, but I was wondering whether anyone has ever come across and art work, books, documentaries or notes from the production of video game or anime music? Specifically from pre 2000.

For example in this interview with Junko Ozawa, she shows her hand drawn "wave library" https://youtu.be/m8z8-SKg3WU?t=409.

I know of some really beautiful anime production artbooks, but I was wondering if anyone has delved into vgm in kind of the same way? I know they’re not going to have the same visual library to draw from, but it would be really interesting to see how the 8bit and 16bit generation producers worked.

And similarly with Anime. This is Tsutomu Ōhashi visual representation of his modular music system he created for the Akira OST

any suggestions welcomed..

———- Post added at 10:15 AM ———- Previous post was at 10:07 AM ———-

Or feel free to post any recommended sources for video game ephemera artwork.. posters, promo material, the more unusual the better.