Yes and no. Currently GeoTour Creator supports adding a "heading" value to any tour location. However, this heading value is only currently supported by GeoTour for iPhone, Android, and Windows Mobile.
Garmin devices do not include direction in their TourGuide alerts. However, there is a way to "trick" a Garmin device into making directional waypoints work properly. Read below for more info:
How does it work?
Garmin devices will continue to play a POI audio file until the end of the file. You will receive a chime and the screen will tell you that you're passing a new POI, but it won't stop playing the current POI. When the first POI is done playing, and if you are no longer inside the new POI's radius, the device will not play the new POI.
How do I do it?
You need to create two slightly overlaping waypoints. Point 1 going one direction will activate and it will recognize Point 2 as you enter the new POI's radius, but it doesn't activate because it is still playing Point 1. Point 1 needs to have an audio file that is longer than the time it takes you to drive/walk through Point 2 so that when it is finished, you are no longer inside the radius of Point 2. This way, Point 2 will essentially be ignored by the unit.
For the opposite direction, just do the reverse. You could even use simple music or an inconsequential message to trick the device. We have found that in order to make this "trick" effective, the two points cannot be side-by-side but need to be offset by at least 300 feet.
* Special thanks to AutomatedTours for helping find this "trick"!