Re cloning the existing OS to the new SSD:

Put the new SSD in a USB or FW external enclosure, then use Disk Utility to format it as Mac OS Extended (journaled) and partition if necessary. Go to 'options' and make sure it is set as the first option in the list as a GUID partition table. Then go to the Restore tab in Disk Utility and drag the source (OSX System disk) and destination (new SSD) disks from the list on the left to the relevant boxes on the right and click restore.

Quite a good tutorial here.