Description - What product(s) or service(s) are you offering specifically? Are any patents, copyrights, or trademarks needed? Have they been acquired/filed? What is the size of your business? Where will it be located? Will this require purchasing or building a facility? Will this require leasing a facility? At what cost? Has a lease been negotiated? What personnel will you need? Where will you find suitable employees? What equipment do you need? Will it be purchased or leased? What are the qualifications of your principals? How do their backgrounds promote the success of this venture? Why do they think this will be a successful venture? Possible Data Sources: local Chamber of Commerce; community colleges & local universities; local employee leasing company; real estate agents; US Patent & Trademark Office; US Copyright Office.
While these are easily available online, some of them are way better than the others. A lot depends on the approach that goes into writing the business plan.
Internet Public Library - The Census Data and Demographics (ipl.org)/: An especially useful site that has links to information about countries other than the U.S.
Some of the benefits of software like Business Plan Pro include, but are not limited to, getting instant access to over five hundred sample templates that can be edited directly, allowing you to create the best business plan template for your particular business.