I recommend getting a tax ID so you do not have to give out your social security. You can register for free at irs.gov. Check with your local city offices to see what licensing they require as well as your secretary of state. Depending on the amount of revenue, you may need to do quarterly tax remittals--you can visit with your personal tax preparer for specifics.
You will also want to register your trade name with your secretary of state and set up a separate business checking account.
Question added to topic Home Based Business • December 2, 2008
What sort of licensing do I need to start a personal/business concierge and errand service?
I live in Michigan. Do I need to get a Federal ID number if I will be a sole proprietor with no employees? Will I need to file taxes quarterly? Do I need any special business insurance?