After clicking on the 'Request ICS Download' link at the bottom of this page, you're browser will be re-directed to a page with a form to complete. After completing the form and submitting your Local information, you will receive an email containing a download link. Open the email and click on the link. You will be prompted by your web browser to "Save" the file.
For first time installations or when installing a new server or standalone computer, save the file to the computer where you'll be installing ICS. Be sure to review the install instructions here.