I have a public Google Calendar where I share my forthcoming classes and lectures.
If you use Gmail/Google Calendar, you can subscribe to find out when my next class or lecture will be. To subscribe, click on the bottom right of the calendar, on the little plus sign that says Google Calendar. Then every time I plan to have a class, you can see it in your calendar (the calendar can easily be switched off with a checkbox if you want to mute it).
If you are looking to have me speak for you or your organization, see the Speaking page of my other website.