How strange. Normally the pref pane will add it automatically. Yes,
you can add it yourself. In the Finder, select "go to folder" from the
go menu, then paste in:
~/Library/PreferencePanes/Spanning Sync.prefPane/Contents/Resources/
(Exclude the "~" if Spanning Sync is installed for all users.)
Then, drag Spanning Sync Notifier into your login items list.
Please let me know if that doesn't address the problem or you have
other questions.