Check nursing act for your state there will be a nurse agency act that spells everything out. I'm not sure but I think you have to set yourself up as an agency. I took this route then after six months I started getting interested in hiring employees.
I had worked at many facilities and networked long before I had thought about starting my own company. I also have a good reputation as a good worker. That's opened doors for me. My first contract was actually easy to get and my second one they called me. These were through contacts from networking. I haven't had any luck cold calling.
I've worked on the skilled floor in a hospital and the geri/psyche also med surg if needed. Mostly I have worked nursing homes, dementia floors, assisted living, supportive living, mental illness, I've done a lot of hospice as well mostly continuous care and a couple months as a case manager. I did all of this as an agency nurse.
Might as well start your own agency. You will have your business entity and you alone can't cover all the hours needed. Hire on some good employees make some extra money on top what you would be making. This is my first year at it the first 3-4 months was rough financially but the money is coming in regards now and will be picking up second contract soon and will be hiring cans and nurses soon. It's very exciting and fun.