DND,
The AMV Convert Tool as part of the "
MP3 Player Utilities" are the official converter for the .amv format. The various versions can be downloaded from
here.
You can also download "
AMV Studio Utilities 1.1" or "
AMV Studio 3" from the same place
here.
They are essentially the same thing.
The .AMV (Actions Motion Video) format is specific to Actions Chipset players so they would be the one releasing the software to convert to that format and would update it.
Hope that helps.