Do a port scan and see whats open. Try to unc from the run line and look at the hidden c share if its a windows box. Is it in the same layer 2 network or is there a gateway between you? If L2, ping it, that'll add an arp entry to you're machine, issues the arp -a command to view the MAC, then use your network equip to find the device by MAC. If over L3, do a tracert and narrow down which hops it uses.