How much Applecare do I have left?

I recently picked up a second hand MacBook Pro with Applecare. It's an older Core Duo model (2.16GHz). Based on the discontinuation date, I would have assumed the Applecare warranty would have expired awhile ago, but it didn't. Here's the problem, though. If it has an EXTENDED Applecare warranty, it will be covered for a while longer, but when I enter the serial number in the Apple Support page on the web, all I get is a confirmation that the warranty exists. It does not tell me when it expires. I have no idea when it was purchased, and I have no idea who might have actually purchased the warranty (if someone even did.)

So how can I get an expiration date for my computer's Applecare? Should I call Apple, or can I get this info online somehow?