Hey,
I'm having a hard time finding info on this online, anyone have any ideas? I'm at a loss!
Thanks so much

its quite simple in the theory, but tricky in practical usage.
assuming you use pix_multiblob for tracking
you will get xy positions for the tracked blobs.
to trigger a button, simply compare the xy position of the tracked input stream with the xy pos of your button. when x && y values are in a specified treshold, the button is made active.

but the trick part is to get propper xy values from the tracker.

you cant just say: lets do some motiontracking, but you will need to know what to track...hands? hole body? multiple persons?
depending on what you want, you will plan the setup, as the most important thing is to come up with a solution that gives you the best results. be aware that you wont be able to track features in any situations. Its very much a process of trial and error
there are many tricks to get good video material that can be tracked. background substraction, just to name one. Also there are many enviroment variables that can mess up the tracking, for example changing light situations...noisy background

tracking will be good if you have maximum control over the scene.
for example
you have a stage performance with black walls and a white dressed actor.

software i can recommand
eyesweb, openCV, Libfreenect (kinect)