How to find my wireless router network password?

I can't remember how to get on the page about my wireless router. I know you're suppose to type in your own ip or something in the address bar but since that's not working what am I doing wrong? I just wanna find the password I set up for my wireless network. I forgot it. :((
Update: No what happened was I forgot my Network Key. I call it password cause that's basically what it is.
Update 2: Everytime I try typing in my Ip in the address bar I get the dreaded "This page cannot be displayed".
Update 3: Thanks Bob A! It worked, thanks so so much!
12 answers