The majority of laptop manufacturers now include the computrace tracking and theft recovery within the BIOS - you can pay an annual charge if you want this option. In the event your laptop gets stolen, computrace can track the ip and address as soon as the laptop connects to the internet, get the police involved, etc.
You also have TPM which is a chip that encrypts all your data so that if your laptop ends up in the wrong hands, they cannot obtain any data from it. I know Dell and HP offer these chips on some of their laptops.
Here is a nice paper that looks at TPM, Biometrics, and Encryption:
http://www.full-disc-encryption.com/...mozTocId271316
With regard to batteries, I usually purchase an extra battery when I buy the laptop, and normally go for the larger cell battery available. In any case, I would always purchase spare batteries from the original manufacturer or their preferred resellers - I would'nt want to end up with a fake battery that is likely to melt/explode!
TEk