At the top of the page you will see BC Doug for click on it then Click on the conversations button. A screen at the top of the the box it will say start a conversation click on that.
Isn't there an option for members to chose "not to receive PM's" or does everyone have access to send you a PM?
I'm glad that you brought membership dues up as it is that time of year again. Well, errr....every year between Jan and Dec I guess.