The most common problem with wireless cards is that they require non-free firmware blobs. These used to be packaged with the kernel but Debian has packaged them separately for the past couple of releases.
The easiest thing you can do is perform the install using a wired network which is much less likely to require non-free firmware. Once the install is complete be sure to install the firmware-linux-nonfree package before trying to use your wireless network. As the name suggests, it is located in the non-free repository which you will need to add to your sources.
Good luck!