You can use something like this:
ForceGuest/Activesync Keys. The download is at the bottom of the page...
It will allow you to make all users walk up to a single machine, sync (as guest - without having to answer any questions), and it can run a command on sync start and sync stop (Such as: open a window in windows explorer with instructions and the file to download)...
Hope this helps...
Steve
Only problem: either use IR or make sure you have a cradle for all of the different types of Pocket PC's you have...