IPv4 address, and how to find on Ubuntu

i remember that on Windows 7, i had to go to my network properties, and find the IPv4 GATEWAY address, to change my modems settings...how can i find this on Ubuntu?i need to figure out which port i mapped for UTorrent...lost my 32bit disk of Windows 7. ;-;

ifconfig eth0

i got the following from that command...ryan@ryan-laptop:~$ ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:26:9e:47:84:f7
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Interrupt:31ryan@ryan-laptop:~$so what's my IPv4 address?

you dont have one on eth0, do you know which interface you're using? try eth1, or if you're using a USB modem or dial up, ppp0Alternatively just ifconfig should show all the interfaces.

actually, never mind...i couldn't run Windows 7 in a VM, so i switched back. T_T