How do I transfer my Aperture 3 application and Aperture Library to a new Macbook Pro?

Hi,

I had a white Macbook. I got Aperture 3 when it came out. However I just bought a new Macbook Pro last month and am having trouble getting Aperture over to it.

When I plug in the serial number I have when Aperture opens on my Macbook, the Macbook Pro won't accept it.

How do I move my Aperture Library and the Aperture 3 application over to my new Macbook Pro?

Also, my photos are all referenced masters on an external hard drive.

Any help would be greatly appreciated! Please!

Sloane