Normally the wep key is not a default, most wireless access points turn this off and it's a setup item.
For the ip, 10.1.1.1 or 10.0.0.1 are the most common ip settings for these, it will always give the default in the manual or a google will give it to you.
And admin, admin will get you into most of them.
WARNING - This may really piss off whoever set this access point up. !
If you press and hold the reset button for AT LEAST 10 seconds, and this may require a paperclip, this will return the access point to it's default settings, can be handy if it's been setup and no one can remember the password.