Only broadband is wireless. Dial-up is wired. So you need to connect you laptop your phone-outlet with the cable that fits the dial-up modem port in the laptop on one site and your phone outlet on the other side.
Such an RJ11 plug looks like a RH45 plug used for Ethernet, but is smaller. It's smaller of the two shown in http://www.cable-trader.co.uk/items/rj11-plug-to-uk-telephone-socket-adapter-cable
Just take your laptop with you to any computer or phone store and they'll have the right cable.
We have a Toshiba Satellite L450 with a dial up modem port I have called Toshiba's tech support twice and tried to find an answer inline to no avail. I got 2 answers. The first was to buy a RJ 15 adaptor (which I have not been able to find online or in local stores). The second was to buy an external modem. I would appreciate any suggestions or advice. Thank you!