EricPriest if the serial number is registered on http://www.adobe.com/ then it is likely a retail serial number. Volume license serial numbers are located at https://licensing.adobe.com/. You can find more details at Find your serial number quickly - http://helpx.adobe.com/x-productkb/global/find-serial-number.html.
If you wish to purchase a volume license for Photoshop Elements then I would encourage you to contact Adobe directly or an authorized volume license reseller. The copy you received from Best Buy is likely a retail version suitable for use by one individual to utilize on up to two computers.