There are plenty of tools and software packages out there that will monitor your Android phone and help locate it in the event that it's lost, but until now we've not heard of any official solution from Google themselves. That's about to change according to the official Android blog, as the Android Device Manager is set to launch later this month.
Built for devices running Android 2.2 or above (that'd be about all of them) Android Device Manager is said to have tools to help you locate a missing phone by sounding the ringer at max volume, tracking its location if it's out of earshot, and a quick and easy way to remotely wipe your personal data off the device if you're not able to recover it.
Many of us have been using some of the great third party tools for this for a while now, but we're still excited to see an official offering. We'll have a good look when it becomes official.