Small Business Licenses, Regulations and Permits
This is the "icky, yucky, pooh" part of business. You started your own business to be your own boss, do what you want to do, or maybe get rich. You didn't start your business to learn about the wonderful world of government small business regulations, forms and licenses!
Yet, you must take the government seriously. You must fulfill your obligations under Federal, State, and Local Laws. Failure to do so can have very negative consequences!
First, I recommend picking up a copy of Small Time Operator, which does a good job of discussing most of the forms and regulations you will face. Then, you should contact your local and state governments to see if they can send you information about starting a small business. See the State-by-State Guide to Starting A Business. The IRS and the SBA are also great sources to learn small business reporting information.
Get it from the horse's mouth. Don't rely upon Uncle Fred's interpretation of when you are obligated to use forms 940 and 941 and when you aren't!