The way I'm approaching it with my cocktail cabinet is using the Opti-Pac optical encoder. It makes the trackball look like a mouse to windows. On top of that, you can wire in any button to work as the left or right mouse buttons.
While I don't have the trackballs hooked up, I'm still looking for them and don't want to pay $125 each for a 1.5" trackball. However, I do have my spinners wired up to it and have the buttons wired into the Opti-Pac and the I-Pac.