In my experience with users and participating in online forums and mailing lists, one of the most common questions that users of Mac OS X seem to have is 'How do I copy my Mac OS X installation from one hard drive/computer to another?' Users generally fall into one of two categories: (1) people who have bought a new (larger) hard drive and installed it in their Mac, and want to move everything over from their old hard drive to the new one or (2) people who have bought a new Mac and want to copy Mac OS X and all their files and software over from their old Mac to the new one.
Transferring Mac OS X between Computers or Hard Drives