The business plan itself will have the same basic elements that are typically found in most plans. While the business you are in may be unique, the general components of a business plan stay roughly the same.
To get over writer's block that sometimes accompanies writing a business plan, you might want to start with the management team section. After all, if you're working in the business yourself, you should be able to provide your background and qualifications. That's often a good way to set started putting pencil to paper, so to speak.
I also recommend that you start at our “How to write a business plan” page here: