Microsoft has just posted today some documentation about Live Meeting API
Maybe you can find your information in here
http://www.microsoft.com/downloads/details.aspx?FamilyID=429e61d6-a172-4bcc-9184-d5f34e9d5e30&DisplayLang=en
Office Live Meeting 2007 includes an API for using external programs to perform some of the functions available through the Live Meeting 2007 User Interface. This API Reference Guide is intended for engineers, developers, and programmers who will design, implement, and test software that uses the Live Meeting 2007 API. XSD files are also included in the download