What needs to be installed on the other computers? MC17 as well? Where does MC Jukebox come into play? And whats the best way to link the clients to the server to share the library?
Clients can be MC17 as well. MC license allows multiple installations within the same household, within reason. MC jukebox I believe is a stand alone player, if you have an MC17 license you don't need MC Jukebox.
A client running MC17 can connect to your MC Server once you've done the steps in JimH's post. Go to File/Library/Library Manager. Click on Add Library and type in the Access key you got when you enabled Media Network on your server. It takes a few seconds but then it should connect and load the remote library.
If you want to change tags and stuff remotely, you need to enable Authentication on your server under Media Network settings. On a client you need to then go to Media Network settings and under Client Options, enable auto sync with server. Once you enable authentication though, it counts for all clients and they will all ask for the credentials upon connection the first time, you can have a client remember the credentials though.