What software is available for iPod music, contacts and calender syncing with an iPod Mini 2G?
You can use media players like Amarok, gtkpod, songbird and Banshee for iPod synchronization similar to itunes.
Amarok - Supports synchronizing, retrieving, playing, or uploading music to the iPod.
Banshee - Allows the transferring of songs, videos, and album art to and from the iPod.
gtkpod - platform independent Graphical User Interface for Apple's iPod using GTK2. It supports the first to fifth Generation including the iPod mini, iPod Photo, iPod Shuffle, iPod nano, and iPod Video etc.
Songbird - iPod device support via community extension. It is a great music organization tool with a variety of extensions.
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This is a very limited answer - based on my experience.
Try Banshee/ gtkpod for syncing music. They do a reasonable job.
Contact and calendar - dont know. But dont think there is any easy solution.
And yes - it has worked for me on my iPod classic. YMMV on iPod mini 2G.
Banshee works beautifully and allows for reverse sync as well. I think Rhythmbox also works fine, but I haven't used that since 10.04 Lucid
iPod Mini is old enough to work with almost any player claiming iPod support. It would make sense to use Banshee if you already use that for music, I don't think there's anything any other apps can do which Banshee can't iPod-wise.
You can use gtkpod - a simple GTK software for iPod.
sudo apt-get install gtkpod