There is no one single format that a good business plan must follow, but please note that there are certain components that should be included if they can be found. Also, this is not an exclusive list of resources, but should get you started in the right direction.
There are several factors that can help determine which resources to use when creating a Business Plan. Established companies will obviously have quite a bit more information available about them. Information for start-up companies will often have to be estimated based on things like industry averages, competitor data, and demographics.