Well, I am pretty sure you heard of this Sub-Culture.
Basically, Industrial is a cross-over of many other fashion; Cyber-Goth, Skinheads, military, Cyberpunk, Bikers, Goth and etc
Well, the basic clothing usually goes from Black Band T-Shirts up to Fancy Trench coats. Boots is a vital thing in this sub-culture.
Metallic assortments is a crucial component as well.
I won't say any more, you can easily dig it up in the Net.
I can say I am an Industrial. Wearing a Steel toe boots, Black-Cargo pants and Black T-Shirt, some small chains around here and there, some eccentric hairstyle done with Gel and Spray. And that's about it.
If you need to think more, think of mixture of Marylin Manson and Wayne Static.
Any comments, critique and any other thing as of course welcomed.