I dug a little deeper and came up with the full list of FileFormat extensions.
http://msdn.microsoft.com/en-us/library/bb241279.aspx

enjoy.

"JNW" wrote:

I've been to http://www.rondebruin.nl/saveas.htm and have used the save as
code before. But I can't find anywhere the FileFormatNum for .xltm files.

Does anyone have a comprehensive list of these format numbers?