Most companies in America are the equivalent of garage businesses with no corporate structure. That works fine for most people ... until you need to hire someone, take out a business loan or you get sued. Business incorporation provides you legitimacy, and some legal protection. Sure, there are legal forms and paperwork to complete, and you will need to ensure compliance with a formal set of rules (most of which you're already following,) but the benefits will easily outweigh the nominal cost of incorporation.
Running a business doesn't stop until the business stops. You can start a company faster and easier in the United States than almost anywhere in the world, but getting it right takes a plan. You'll need to consider whether you need a business loan, temporary or permanent staffing, whether you're going to use a public relations company to get word out about who you are, business insurances, data backup, where are your customers coming from? Will you need to contract with a lead generation service? And this is just the very tip of the iceberg.
Separation of personal and business finances is essential for any business owner, and gives you a little protection from the IRS. How do you open a bank account for your business? It's not quite as simple as wandering into the local branch of the big bank on the corner.
If the bank won't lend you capital, how do you finance your business? We're assuming you don't have a rich Uncle Tony and don't have a winning lottery ticket in your pocket. Your choices after that are institutional lenders, private lenders, account receivables funding, or selling a part of your business. Finding capital can be tough, but here's how to find a few, and how to be professionally prepared to answer the tough questions a lender might ask.
What do you really need to know about tax law? Keep solid records, separate your personal finances from your business finances, and if you take your business seriously, get an accountant.
What do you really need to know about exporting your stuff to other countries? Learn to work weird hours and to spend some quality time with your voice mail system.