Some useful books are:
The Entrepreneur's Guide to Writing Business Plans and Proposals, by K. Dennis Chambers. Praeger, 2008.
CARR HD 62.5 .C423
The Ernst & Young Business Plan Guide, by Brian R. Ford, Jay M. Bornstein, and Patrick T. Pruitt.
CARR HD 62.5 .S556
How to Write a Business Plan, by Mike McKeever. Nolo, 2007.
CAMDEN HD 30.28 .M3839
Anatomy of a Business Plan : A Step-By-Step Guide to Starting Smart, Building the Business and Securing your Company's Future, by Linda Pinson. Dearborn, 2005.
Excellent guide to the whole process. Some worksheets and forms, both blank and filled-in, are provided.
DANA HD 30.28 .P5
Business Plans Handbook. Multiple volumes. Gale Research, 1995- .
A compilation of actual business plans developed by small businesses throughhout North America.
CAMDEN RESERVE, DANA REF, CARR REF HD 62.7 .B865
Entrepreneur Group's business start-up manuals This large set has business plans for specific types of small businesses.
CAMDEN RESERVE, DANA HD 62.7 .A32
You can consider this business loan checklist to Gather the Info You'll Need from the Small Business Administration, as well as 10 Tips for What a Lender Looks for in a Business Plan.
And here's an online book: How to Prepare and Present a Successful Funding Request.
A variety of business plans and marketing plans are available on the Internet. Here are some sites to visit for help with writing and developing your plan.