David Jones has a very good video up on YouTube about how to go from a working prototype to high volume manufacture. The video is a bit over 50 minutes long so be prepared to put some time in. The information is oriented to the novice (and he failed to mention automatic pick and place machines for through hole components - does anyone still operate those?), but I found more than a few helpful hints and things to add to my checklist even though I have been at this for over 40 years. Plus there are a number of other videos - long and short - about the electronics industry and designing electronics on the sidebar at YouTube.
Dave also has a blog - the Electronic Engineering Video Blog (EEVB). David also mentioned to me (via e-mail) that he has an Internet radio show/Podcast. The Amp Hour. Not to be confused with the company similarly named. I found the videos to be more engaging than the audio. But that is just me.
M. Simon's e-mail can be found on the sidebar at Space-Time Productions.