I started keeping a text file with all things I read and another one for audiobooks. Since Obsidian came out I use it to edit my file and link books together.

I use the following format:

[[title]] by [[author]] (date finished)

That way I generate a separate file for each book where I can keep notes and my rating. I also keep a separate file for each author so I can easily link all the books/short stories/essays etc by that author in one place. Obsidian is bloody awesome.