For those interested in the Apple Serial Number Info site, created in 2008, it is AppleSerialNumberInfo.com. A similar site that likewise provides Apple serial number information is Chipmunk, offered in English and Dutch.
You also may like EveryMac.com. Founded in 1996, EveryMac.com can decode Macs by serial number and other identifiers, but it also has Mac answers, comparison, prices and more. The EveryMac app may be helpful, too.