If your marketing materials are sufficiently original they can be protected by copyright.  Every page of your website should have a copyright footer "Copyright (year  of creation) (your name).  Really great materials should be printed out and submitted with a copyright application, the required fee, and the fee for expedited processing  (to get your material registered more quickly) to the Register of Copyrights.  You can do this online.  Why should you do this? Because you need an official copyright registration issued before you can haul the offender into court.  The registration also allows you to sue for statutory damages.  Next if you brand your services you should apply for a trademark.  This takes longer, however it provides you with an avenue for stopping disparaging behavior once you finally get your service mark registered.