Photoshop CS5

Hello - I purchased photoshop CS5 extended a while back.   I own the license, and it is prior to the Adobe charging a monthly fee. My MAC died and I am trying to install CS5 on my laptop using the license that I already own.   I want to deactivate the license on my Imac desktop, and activate the license on my macbook pro laptop.  I cannot find the option to download CS5 anywhere online.   

Thank you!