If you want to see both machines on network, make sure you have the same Workgroup name on both of them.
1. On your desktop, right click on "Computer" and choose "Properties"
2. From the left hand side, choose "Advanced System Settings"
3. Go to the first tab "Computer Name" and click the "Change" button at the bottom
4. Rename BOTH your machines to a name of your choosing (workgroup or home)
5. You'll have to connect your tower PC to a screen in order to do the above changes