The older stories are in various archives on spanko.net. There's a post in the main story forum where there are indexes at
http://www.spanko.net/spanking_forums/viewtopic.php?f=3&t=69 - and one of indexes links to where all my older stories.
I believe that all of them are also on this site, but they are in a different format (a message on a forum as opposed to a popup story window).