Essentially I'm answering my own question here, but want to provide this info to anyone else who might need it. I need all the valid IP address ranges for Google Apps mail servers.
I'm configuring a firewall to only allow incoming SMTP from our Google Apps hosted (POSTINI) email and want to allow only the expected servers to connect to our internal server for delivery. In trying to setup the rules in our firewall, it does not accept CIDR notation for the allowed IP address ranges. Thus I have had to convert them from the CIDR addresses provided by the article:
Google IP address ranges
NOTE: This is not a duplicate question. The article linked to as a duplicate reference is "how does IPv4 subnetting work". This is not what this question/answer asks or answers. This article is to save others the time to do each of those conversions manually from Google's published list of addresses if they have network equipment that doesn't accept CIDR notation.