Another consideration. Should the business plan be a document that is focused on selling an idea for a product or service? For many years I worked in a company that did not want anything in a business plan that could be construed as showing a bias towards or against a project. The mantra was to only present facts in the business plan. The Operations Research Department was there to review the analysis as being unbiased. To handle the "what if" scenarios or sensitivity analysis we prepared a supplemental analysis documents which were mostly financial oriented. Personally, I like a factual approach and use the presentation of the final document to point out the conservative aspects of the content.
If you are one who is intimidated by the blank page, never fear! There are several good software packages that will guide you through the process, such as Business Plan Pro Complete from PaloAltoSoftware. Business Plan Pro Complete walks you through the entire planning process and generates a complete, professional and ready to distribute plan with a proven formula for success. The planning wizard makes it a snap to get started since you simply answer yes or no questions to create your custom business plan framework. Bplans.com offers free business plan samples and how_to articles as well as a wealth of other information. It is definitely worth taking the time to checkout. Microsoft Office Online Templates also has a variety of free templates to use with their products. The wizard indicates the information you need and you fill it in as you go.