1. Do you have a DHCP server on your network?
2. Did you configure the empeg to use Ethernet (you need to connect with USB/serial once to do this)? If you've got a DHCP server, there's a setting for that. Otherwise, you need to assign a static IP address.
3. Is the address assigned by your DHCP server (or yourself) on the same subnet as your PC? Emplode looks for the empeg by broadcasting a discovery packet on the local subnet. If the empeg isn't on the local subnet, it won't respond.
4. Having configured the IP address of the empeg, can you ping it from a command prompt?

Roger - not necessarily speaking for empeg