Home modem doesn't show on network manager?

Basically, I've just moved into a shared, rented accommodation and was promised by the landlord that broadband would be available to me. However, the modem doesn't show up on the network manager bit on my netbook. I've tried manually setting up the modem manually using the username and password but it didn't work. I knw for sure that there is broadband in the house because my neighbor has no problem connecting to it.