Yes unfortunately for you, you arent going to find anyone on here who is going to tell you how to find out a wireless password. (at least not in public).
As above if you are allowed to have the password then ask someone if not, then either do the right thing and stay off it or find another way to get it but you risk the consequences of which i do not know what the are?
My sensible side would tell you to do the right thing and ask for the password if you don't get it .. . . . . .well use an iphone or an android phone as a hot spot