Legal Question in Intellectual Property in Kentucky

Whether you need a business license depends on your county. Here in Lexington, we have a $100 annual fee. If you're a sole proprietor, you don't need to do anything special. If you have a partner, you should get a partnership agreement. I would suggest speaking with a CPA about the tax advantages for business organizations, whether or not you should form an LLC, etc.

You can copyright the image of your bumper sticker, but it isn't necessary. It is still your intellectual property regardless, the registered copyright merely makes it easier to collect for infringement and provides a basis for damages.