are you looking for the default address of the rotuor so you can get into its menus etc to setup ports? or are you looking for the local ip address that the routor assigns to your computer or are you looking for your internet ip address?
default address can be found by usually looking under the routor. if not type in the manfucaturers name with default ip address and then google it or by going to command prompt and typing in ipconfig and it will be the number next to default gateway
local ip for your computer can be found by typing ipconfig in command prompt. (it will usually look like 192.168.#.#) similar to your default gateway address
and your internet ip address can be found by going here: