Out of the box <external> objects

System

Is there anywhere that lists and explains what out of the box objects are available to use in the content xml area? com.interwoven.livesite.external.impl.LivesiteSiteMap is an example but what are the methods available to it? What else is there? I dont want to have to write it if it already exists but apparently I have no clue of where to look.

Thanks for any input. And if I need to rtfm the one to read would be nice as the SitePublisher Developer Guide does not seem to list this info.

Forgot to put the version we are using SitePublisher 6.7.2 sp1 and what ever LiveSite goes with that