Hello Benjamin,
The two IP addresses Kim listed in her post were the most common ones used by router manufacturers. Private address ranges: 192.168.0.0 to 192.168.255.255, 10.0.0.0 to 10.255.255.255, and 172.16.0.0 to 172.31.255.255 are all available for use in private routers. To find your router’s address open a command prompt and type “ipconfig” (w/o the quotes) and press enter, the address of your router will be listed as Default Gateway. Enter that in your browser and your router will respond. If you received your router from your IP your userID and password should be listed on one of the documents left you by your provider.
You can also look up the default ID and password for first connection out of the box by looking in your manual or downloading it from the manufacturer. If that is still your router’s password change it immediately and don’t lose it.
You should definitely get a manual for your router.