We are starting a mom and pop bimonthly local publication. Since we're so small and have no employees, is it necessary to file for an LLC or S corp.?
It is not "necessary." It may be advisable, though.
Nope. The reason you would want to form an LLC or Corporation is to protect your personal assets. Like, if someone sues you, they can only recover the assets of the business, not your home, cars, investments, etc.
It depends upon your exposure to liability. I would check out the U.S. Small Business Administration's website for additional information about the pros and cons of each business structure. Please feel free to contact me if you need legal help with your business formation or contracts.