Should this display on the EXTENSIONS page report the IP address of the server?
Not necessarily, it will show the address that chan_sip is bound to, which you can confirm with:
asterisk -rx "sip show settings" | grep Bindaddress
so my bind address is 0.0.0.0 wit port 5060?
0.0.0.0 means ALL addresses on the machine. If you have 5 ip’s assigned it will listen on all