How to obtain a security key to a Motorola router box?

I just got a router box because i wanted to use wireless, but someone threw the box away before i could get the password from the instruction manuel. How do you get the security key without out the manuel. I've tried for hours trying to find a way to find the key over the internet, but i'm extremely computer illiterate and don't understand half of what anyones talking about. Exactly how do you get the security key? Its a motorola model: SBG901. Thanks for any input.|||If you have never set a password, then it is usually "admin" without the quotes. Resetting Motorola router http://www.cradlepoint.com/knowledge-bas鈥?/a>