Hi
Well I suggest you start by creating an object design which will store the data you retrieve from the database in memory.
You will be adding controls to a form at runtime. You will have to decide on a general algorithm which will dictate how controls are arranged on the form.
Next looking into the drawing classes of .NET, these will enable you to draw pretty much anything on a form.
MSDN
If your network is very large think about how you may design your objects in such a way that different regions of the network may be viewed individually.
If you want real time updates of your UI based on the state of the network you will also need to look at network communications, the NetworkInformat ion namespace will help with this
MSDN
Also for real time updates look into threading
MSDN
Read the MSDN entries if you are unfamiliar with any of the required components and create a design with clear goals of what you want to achieve.
Try to create the app even if you fail, its the best way to learn, then post any problems/questions you may encounter and we'll have a look at how to help you out.