Lacie Porsche 3TB desktop drive setup will not set up on iMac!!!

I have a 7 year old iMac running Mac OS X v10.6.8 (Snow Leopard). I bought a new LaCie Porsche Design 3TB Desktop Drive. The drive appears on my desktop. When I click the LaCie setup button I get this error message: "You cannot open Lacie Setup because it is not supported on this type of Mac". I need this drive to work so I can back up all my files asap. I can't find any help on how to make this hard drive work for me. I need help now please and thank you!!!