Augmented Reality for desktop app

Hi, I've already worked on a few apps for mobile devices using the Qualcomm Vuforia plugin. I'd now need to build an AR app that runs on a windows machine, either standalone or in the browser (via plugin). I did some research and found a few non unity based solution that don't look as advanced as the Vuforia version. On the Unity front there is the ARToolkit which is quite old now and I am not sure where to start with this because there doesn't seem to be a proper tutorial or documentation anywhere.

So the actual question: can anyone recommend any plugin or program or has more info on how to use the ARToolkit in Unity?

Thanks!