Is there any way to track motion realtime with webcam? like on xbox with kinect.
Yes, I believe there is a public library for that (i.e. plugin for Unity), although I can’t remember the name.
There is a product called iPi Motion Capture that does trackless motion capture using regular webcams or one or more Kinect devices. I don’t know if it will suit your needs sense your question is light on the details, but hopefully it will help.