I don't know about the laws in your state, so I can't really tell you if it would be ok to use the same ID#.
As far as wholesale fabric distributors, the only one I personally know about is Golden d'Or in Dallas. I have only purchased retail from them so far, but know they also have a wholesale side.
Do not know what their criteria for wholesale would be regarding volume, etc. I do feel sure that you would need to buy a whole bolt of any fabric you purchased. Whether you would have to have a certain # of bolts per order or a minimum opening order or a certain $ figure per month/quarter/year, I couldn't tell you.
I'm sure others on here will know more about this than I do.
Good luck in your endeavor!