NFTE publishes several books that can guide you through the process of developing a business plan. Visit http://www.nftetechnology.com/products  for more information and to purchase materials.
These organizations offer a wide variety of workshops and conferences, financial assistance, directories and other resources that can help you as a small business owner:
US Small Business Administration  - provides programs and services to help small business owners, including information about financial assistance, trainings and counseling, regulatory information and contract opportunities.
National Association of Small Business Contractors  - a trade association that supports the interests of America's small business suppliers who provide goods and services to government, prime contractor, and corporate buyers.
StartupLoans.org  - a resource that provides factual information about the lending industry, and resources for businesses such as incorporation portals, state by state resources, and free publications for e-books with common trends and business research.
US Chamber of Commerce  - the world's largest business federation representing the interests of more than 3 million businesses of all sizes. 96% of US Chamber members are small businesses.
Women Impacting Public Policy  - an advocacy organization for female and minority small business owners.
IBM 100  - to celebrate IBM's 100th anniversity they are sharing a Student Entrepreneurs guide on their website that you can download. This toolkit provides you with many great resources on how to turn an idea into a business.