We have a part time metal art business since I'll be fully employed for the next two years. All of my business has been 'word of mouth', although recently we have attended one motorcycle rally, and one craft show, got an Internet presence and even set on the side of the road two times. Business was slow to start, but since I was working anyway, that was fine with me (did my cutting on the weekends).
Well it's grown to the point where I'm either referring business to my competitors, or refusing work. Once I retire, I'll rethink that, but ultimately, my goal is to make just enough money to supplement my other earnings...and take trips. Husband/wife business with no desire to hire help.
As far as taxes and the government goes, it's not all that complicated, or time consuming, and there is even the advantage of having a small side business, with your available tax write-offs.
Bottom line...I'm happy and glad I got into this line of work.