I assume that you mean that the laptop is asking for a password and you don't know what it is?
I have no intention of posting on an open forum how to hack passwords and I hope that no one else will either. To do so would be a recipe for even more stolen laptops, which we do not need because violence is often used if owners resist.
Take the PC with proof of ownership and ID to a Computer shop and I am sure that they will attempt to help you.
T, December 2009