I hope this will make it somewhat more straight forward for you.
You will need three files that are on your distribution disk.
/extra/source/intel-wlan-ipw3945/microcode/ipw3945-ucode-1.14.2.tgz
/extra/source/intel-wlan-ipw3945/regulatory-daemon/ipw3945d-1.7.22.tgz
/extra/source/intel-wlan-ipw3945/kernel-module/ipw3945-1.2.1.tgz
Untar these three .tgz files in a directory where you can play with them.
In the directory created when you un-tared the microcode tarball, copy the file named ipw3945.ucode to /lib/firmware.
In the directory created when you un-tared the regulatory-daemon, copy the ipw3945d to /sbin
in the directory created when you un-tared the kernel-modules, run the following. make, make install, depmod
Now, as root enter: modprobe ieee80211
Then enter: modprobe ipw3945
Then enter: /sbin/ipw3945d &
Then enter: dhcpcd eth1
You should now be connected to your neighbors WiFi