What are the laws and regualtions for starting a drafting firm or a drafting business.

You can't legally practice Architecture without a license if that is what you mean. You can draw houses without a license but there are limits. If you are going to draw for Architects as a subcontractor it is just like any small business. You'll need software and licenses for that software.

If you are asking about this concerning a particular location, then for the possibility of finding out about the laws and regulations for a certain area, it would help to know where the location is about which you are inquiring.