I can't think of any place where you will get a secure WiFi connection. If you must do this then talk to your network admin and ask him to setup a VPN on your computer (both office and your laptop). That will give you a secure connection via any WiFi network.
When i need a secure WiFi connection, like buying something with a credit card or what ever i just tether to my cell phone. That is a encrypted data connection. Check to see if there is software available for your data enabled smart phone that would allow you to tether to it for a short period of time. It will not be fast but the only people who could see it would be your cell phone provider but you would be one of several million users and i highly doubt they would care enough to sift through your data... If you seriously need a business center then any convention hotel will have one. I have used the ones at the GF and the CR just be aware if you need any materials they are seriously expensive but in a pinch it works.
