I would suggest going to your local Small Business Administration Center. Each state has it's own guidelines regarding what is needed in order to do business. They should have all the information that you need to figure out what you need in order to get the ball rolling.

I would also look into getting into federal sales as well if you have a unique product. The best place to look into federal inquiries is http://www.fedbizopps.gov/.
Being in Hawaii, I have had a lot of experience working with the federal government and it can be a very profitable venture.

Hope that helps....