So I'm going to post an update to this, and the download page for the Logger, but it appears since Steam's newest Friends layout update, you can no longer log your messages. I did a small amount of digging but I didn't find anything to replicate this software with the current versions of Steam.
I'll leave the download up since it seems to be the one of the last places to get this tool anymore.
I'll leave the download up since it seems to be the one of the last places to get this tool anymore.