You need to talk to Dell: They sold you the software, and they are the ones who need to provide you with the installer (either via download, or on a disk). Chances are that you do have the installer on a "recovery disk" - a DVD that installs the software that was available on the laptop at the time of purchase.
If you don't already have that recovery disk, Dell needs to provide it (or the Acrobat installer).
Karl Heinz Kremer
PDF Acrobatics Without a Net
PDF Software Development, Training and More...
http://www.khkonsulting.com