I've recently built enough cellar racking for about 400 cases of wine.
How big is your room? Do you plan to create a passive or mechanically
controlled space? Do you want single bottle racking and bins? I can
send you some photos and this may help you start your plans. It's
possible to save some money building these yourself but I agree with
Guess Who, build them if you like to build.

Where do you live, and do you lock your wine cellar at night?