connect to your network currently?
Having two routers on a network, while possible, is usually a recipe for problems especially if they are both acting as DHCP servers.
It should work wired in the same way as it does wirelessly
I have my music with iTunes installed on a PC desktop that is cabled (cat5) to a router. Can I cable the AirPort via Cat5 to the same router and use that configuration to push music from iTunes to the Stereo receiver?
All the configurations I see in the AirPort documentation show the input to it being wireless.