How do I download ARX CoSign® Digital Signatures?

I registered and signed up for a newsletter that I didn’t want because this site indicated that I could download ARX CoSign?? Digital Signatures for Microsoft Office for free. All that I am getting is a pdf that has information about ARX CoSign?? Digital Signatures. How do I download ARX CoSign?? Digital Signatures? Was it a trick to get me to sign up? How do I un-register so I don’t get the newsletter?