Adeona is an opensource laptop security program that can help you track down the location of a stolen or lost laptop. You need to install a small client software on your computer that will help track your computer each time it connects to the internet. This data including the IP address that was used to connect can then be used to find the location or user that connected using the laptop.
A concern with other similar security programs is that there is a 3rd party involved that stores your information (no more location privacy). Adeona solves this by encrypting the uploaded data and only allowing the owner to see the location data of the laptop. It uses a community-based remote storage facility, ensuring retrievability of recent location updates.
The Mac version of Adeona also has an option to capture pictures of the user using the inbuilt camera.