You can type “business plan” or “business plan template” into Google or other search engine and come up with thousands of results. Instead of wading through all those results, and sales pitches, here are a couple of resources for standard business plans and advice from the Small Business Administration and SCORE.
The Wall Street Journal has been running a series of articles reprinted from their Small Business Handbook. A recent posting is related to forming an LLC, a limited liability company, and why it is a popular option for small businesses. The article also has links to other articles in the series including establishing sole proprietorships, partnerships and other corporate entities.