During the Viet Nam conflict I spent 8 years in the U.S Air Force as a Warehouse Management Specialist and I couldn't begin to describe how many miles of storage shelves I built during that time.
The product you have illustrated comes in a large variety of factory precut lengths with the rivets already set in place. Typically the sections are available in 12", 18", 24", 36" & 48" and some may be available in 60", 72" and 96". When it is necessary to make a custom length in the field they customarily cut the material to length then drill holes where the rivets would be and use ordinary stove bolts to assemble the rails to the posts. Some of these products also use a different type of rail for footers or headers. While the final assembly is quick and easy it is often a nightmare to preplane and determine the number of pieces you will require in each length.
There is another product called "DEXION SLOTTED ANGLE" That is very user freindly and will produce almost the same end result.
The DEXION SLOTTED ANGLE is simply a ten foot section of steel angle iron that has holes and slots precut in the material. It can be easily cut in the field using any metal cutting tools that you may have, I.E. a hacksaw, or a circular saw, reciprocating saw, jig saw, chop saw, power miter saw, etc that has been fitted with a standard metal cutting blade.
The advantage is that Dexion uses the same material for posts, rails, headers and footers and can be cut in 1" increments to whatever dimension you may require. It is then assembled using standard stove bolts and nuts so the only assemble tool you will require is a 1/2" socket or open end wrench. In practice dexion can be thought of as a childs erector set on steroids but in practice it will produce an end result that will hold up to industrial strength demands. Once you have the frame assembled you would then use plywood shelving in the same manner as for the product you illustrated.
Another advantage of the dexion material is that you can easily put additional dividers between the posts if you need to change the layout on differnt layers of your shelving.
You can usually find Dexion in most of the larger home supply centers although you may get a much better price if you buy in bulk from a local commercial supplier or check for online sources.
I am attaching a link to one site. I just found the site by running a search for Dexioni so I have not done any business with the supplier in the link. Please do not take this as an endorsement for the supplier but it will give you an illustration of the product and approximate costs.
http://www.lkgoodwin.com//more_info/...ed_angle.shtml