Requesting Backup Discs - XP Laptop Inspiron 6000

I am a newbie, and have a problem.  Someone please help!  I have this laptop that was a gift from my brother, who is currently out of the country.  Anyway, I got a virus, and someone wiped out my laptop.  I was going to request a backup disc, but since I did not purchase this, I don't have my customer number, zip, address, phone, etc.  I DO HAVE ALL THE INFORMATION STILL ON THE LAPTOP - THE SERVICE TAG, PRODUCT KEY FOR XP.  My brother is in the military, out of touch, so I can't ask him.  Anyone that can help get me back up, I would be greatful!