Sorry to hear about your difficult situation. Depending on how the computer was formatted, it may still contain some of the files you want back. As EuanC said a data recovery company is your best option. An example of one is:
http://www.data-recovery-direct.co.uk/
I suggest finding a company you like the look of and phoning them up. The quicker the better however, the longer a file is deleted the less likely it is to be successfully retreived. I'd turn the laptop off and keep it off immediately.