My friend has a small tool and die shop where he designs and makes the molds for plastic bubble packaging (and, incidentally, plastic holiday serve-ware). Manufacturing is done elsewhere, but his process is the first.
Does that help?

I used to have someone work for me who was a packaging engineer. I don’t know who he had worked for, but his job was to design custom packaging.
A quick google search for custom boxes yielded this vendor
I’m sure with a little research you could find more.

You go to a commercial printer such as “Triangle Printing and Packaging Company”
http://www.triangle-printing.com/
to order packages, printing, die cutting, and fabrication if necessary.
However if the visual appearance is important (as it is for most commercial products) you should first have a design, for which you should probably see a graphic designer who specializes in packaging.

I use U-line for certain packaging needs. Uline

Product design and marketing for every manufacturer that I’ve ever worked for (more than a few, and in several industries, too) have always included packaging / packing for shipment (and sometimes for retail sale as well) and logistics.

In other words, the product has to be shipped to distributors and/or retailers, and it has to survive the trip. So packing for shipment (and again, also for retail sale in many cases) has to be part of the product development cycle, not just an afterthought. The way Apple packs iPods, for example, and the way IKEA package their RTA (ready-to-assemble) furniture are not accidental or left to chance. It’s part of the entire design of the product.

So if you don’t have in-house packaging engineers, then you select a subcontractor / partner who specializes in this work, and contract with them to participate in the product design and manufacture.

And when your product is utility-size steam boilers, then your product design has to include “constructability” (the thing has to be capable of erection at the jobsite) and all of the pieces have to ship over the road (including over and under all the bridges that it may encounter), on rails, on ships and barges, and it has to survive all of that shipping and handling at multiple points, too. It also needs to include or provide for long-term storage at various places and in all sorts of wet, dry, hot, cold, desert and marine environments, too.

No responsible manufacturer produces something and then pays lip service to, “Well, there it is. Let’s slap a cover on it and throw it in the truck.”

I worked in the manufacture and distribution of small electrical connectors.

Everything was packaged as it came off the automated assembly line or from manual job assembly. When we brought out a new product line the packaging had to either be designed specifically for that product or we used existing packaging. Obviously if we could use existing packaging, such as a 50 piece box or 100 piece box then we saved money by purchasing and storing only one standard box size which reduced our inventory requirements.

When the standard packaging needed to be changed our box suppliers were more than happy to do the new design for us’; after all it gave them new business and guaranteed that we would keep using them as a supplier.

It should be noted most of our custom work was required to be packaged and shipped according to the customer’s specifications as to type of packaging, materials, size, markings, labels, etc.

SRM

packaging plants abound.

“No responsible manufacturer produces something and then pays lip service to, “Well, there it is. Let’s slap a cover on it and throw it in the truck”
@CWOTUS, that depends on the market for the product. What you’re saying is true for a retail free market but not for most wholesale products or for instance military items such as ration meals.
http://i801.photobucket.com/albums/yy293/Bigbrottroy/mres_two_tan.jpg

@JaneraSolomon I can’t say anything about packaging for “most wholesale products”, but you’re incorrect in thinking there’s not much thought involved in the packaging for MREs. Take a look at this for starters (pun not intended).

Functional yes. Decoratively printed, no.

My sweetheart works for a company that prints on the plastics and molded forms for health and beauty products. It’s a very specialized industry with expensive materials and inks. They have salespeople on staff, but also a website to get their name out there. They have very big-name clients though, because what they do is pricey.

If I was a start-up, I would start with local printers, and if they might have additional resources for vendors that have the kind of packaging I’d need.

The company should probably first go to a packaging or branding design agency, as container manufacturers typically don’t have a full creative design staff and only manufacture to supplied specifications.

Also packaging/branding agencies typically know what suppliers to use for specific parts of containers.