Networking :: Configure Wifi Through Console?

I am trying to connect to wifi access point with terminal, I set up my own access point (no encryption or MAC filters) I ran followings commands

Code:

$ sudo iwlist eth1 scanning
eth1 Scan completed :
Cell 01 - Address: 00:11:2F:A2:99:1C
ESSID:"esus"

[code]....

Also I have another question, lets say I am connected to an AP but DHCP is disabled, also there is running web interface on AP throught I can set up DHCP and obtain IP address. How do I know what is IP of the AP which I am connected, is there a solution or I have to reset AP ?

Code:

$ echo -ne {0..255}.{0..255}.{0..255}.{0..255}"
" > addresses
$ sudo nmap -sS -iL addresses