ITunes for 2 devices on 2 computers.

Question

I've had the classic for a while now and learned how iTunes works with it. Now I have added an ipod Touch (8gb). Problem I had was the touch was opened on my netbook at my girlfriends - so I loaded itunes in order to charge the touch. I now have iTunes on both my netbook and desktop. Is there anyway I can have both systems the same for both devices?
I added a few apps and downloaded Airplane to try out the Touch with a movie on my netbook.
I have returned home and connected to iTunes on my home PC and can no longer find Airplane. Presumably it is still on the netbook at my girlfriends.
I am at the stage where I am scared to do anything in fear of losing all my stuff. Still not sure about i-Tunes after a fair amount of time using it. Where did my movie go?
I'm sure others have had similar problems trying to use two devices with one iTunes library on two or more PC's. How does one sync everything without losing existing files? - any pointers gratefully accepted.

Answer 1

*How to use multiple iPods with one computer*
The Apple support document How to use multiple iPods with one computer suggests a number of ways. I use method two (Sync with selected playlists) with a slight twist. Rather than regular playlists I set the grouping field to indicate which users should receive which tracks and create smart playlists based on the content of this field.
e.g.
"Alice's Tracks" is "Grouping contains Alice" + "Kind contains audio"
"Bob's Videos" is "Grouping contains Bob" + "Kind does not contain audio"
Tracks that both Alice & Bob want on their iPods have the grouping set to "Alice/Bob"
etc.
I currently manage our family's five iPods using this system, each getting a different selection to suit their tastes and the capacity of their iPod. An advantage of using the grouping field is that it is stored in file tags (for non-wav audio files anyway) so that it is relatively easy to recreate the playlists should the iTunes library get trashed. Also useful if you move files about manually as playlist membership is preserved when you delete & re-import the tracks.
tt2