Open Question: How can I expand my business and get a credit card to track business expenditures against income?

I want to validate and solidify my business so I can expand and grow. I did really good in 2008, my company is 3 years old, I never tracked my income much I just know it was more than enough to be comfortable. I have never used a credit card before, my credit is insufficient to do anything like finance a car or home and I want to establish an excellent credit score before I start to do other stuff where credit is the main factor and basis of payment. I have a low credit score now and I want to know what the different terms mean, IE revolving credit, insufficient credit, delinquent accounts or any other terms utilized by companies. I especially want to build superb credit and expand my business. My line of work is the entertainment industry.