How to find my AT&T Wi-Fi password?

My Iphone was logged into my wireless internet and my mom forgot to pay the bill, so it was shut off for like a day. I didn't know what was going on, so I logged my phone out of the Wi-Fi. Now, I can't log back in cause I have NO idea what the password is. My computer is still logged onto the Wi-Fi. Is there a way for me to retrieve the password from my computer or do I have to call an AT&T representative?

You can call at&t or go to this website http://howto.cnet.com/...-password/
download the wireless key view follow the steps