There are papers on the web you can download as pdf from the UVI program.
There are system manuals that Friendlies sells.
I don't think there is any single piece of literature that is available for fee that will simply design you a commercial system. There are too many variables involved for a functional one size fits all answer.
If you want it for free, you are going to have to invest much time researching to find all the information you need to learn to design it yourself.
Or you buy a manual or books or go to the training or hire one of the consultants to design it for you (but if you hire some one you will be bombarded with lots of questions since all those variables need to be figured out to design a good system.)