Microsoft Malware Protection Center
It's not specific to OneCare, but works for all of the Microsoft anti-malware products including WIndows Defender and MS Forefront client security since they all use the same basic engines and detections internally.
Last I knew, if you got some malware with WLOC the notification included a link to more information online. This was linked directly into the Encyclopedia pages relating to the specific threat.
OneCareBear