this one will show you how to share your itunes library over a network [a local network, like your home wifi network =]
first thing:
authorise all your machines with the same itunes store account.
then:
- open itunes on the machine where your library is [ill call it the main machine form now on]
- goto preferences > sharing
- tick ‘share my library on my local network’
- pick the things you want to share [probably your entire library]
then: