First of all they can not do whatever they want, especially if you are paying rent. They have to go through formal eviction process to get you and/or your belonging out. They have to follow all the rules up until that point that they would for any other renter regardless if it's a lease or month-to-month.
Go to your state Consumer Affairs website and find out what your rights are as a tenant. While you are there look and see what is and is not legal for your landlord to do.
I'm not by any means telling you to let it get to the eviction process. I just want you to know that they can't just throw you and your stuff out without giving you time and options.