Not really too much you can do except for call the police. But check out these possibilities, they will be a long shot but you never know!
How to Track a Stolen Laptop With a .mac Address
1. Notify your network administrator of the theft. Locating a stolen laptop using a .mac address isn't possible unless the thief gets on the same LAN. This makes recovery unlikely with the exception of a computer used on a college network. The likelihood is much higher if the thief is a student who will log on to the university network with the stolen laptop. In such a case, let the network administrator know of the theft. Supply the .mac address and the network administrator can watch for the laptop to log on to the network.
2. Forget about tracking a stolen laptop over the Internet using a .mac address. Tracking a stolen laptop using a .mac address is not possible over the World Wide Web. This second-level information is not passed through the router to the third-level ISP (Internet service provider).
3. Increase your chances of recovery by preinstalling antitheft software that "phones home" to a service provider or open source software such as Adeona. This allows the original owner to gain IP address information without contracting with a third party such as LoJack.
How to Track a Stolen Laptop With an IP Address
1. Contact your ISP (Internet service provider) to see if the thief has accessed the Internet using your service. The ISP issues a location-specific IP address when a computer accesses the Internet. If the owner of a stolen laptop obtains an IP address assigned to her computer since the theft, then the police can track its location.
2. Investigate whether programs such as Yahoo! Messenger or email software that automatically logs on at boot-up are still being accessed. Contact the service provider with appropriate police report documentation and a subpoena to obtain a recent IP address for a stolen laptop.
3. Use preinstalled antitheft clients to obtain a recent IP address for the stolen laptop. Supply the IP information to law enforcement.