Amanda is awesome.
But it's not necessarily the right thing for your situation. It is intended for network backup of multiple machines. You could use it if you just wanted to do it for the sake of learning new software, but otherwise you probably want to choose simpler tools.
If you assume that you will reinstall in the case of disaster, then you can just backup data using something like rsync. There are incremental snapshot methods that can be used to work efficiently with rsync. For example,
http://www.mikerubel.org/computers/rsync_snapshots/.