I found your post in the off topic folder and have deleted the response that was posted previously and moved this thread to General.
OneCare is available free from partners such as Qwest, if you are a subscriber to their service. If your ISP does not have a partnership deal, OneCare is a paid subscription. You may find a retail copy at a reduced cost and occasionally a rebate is also offered, making a 12 month subscription free or nearly free.
-steve