The ndiswrapper package is a great invention. Many laptops come equipped with wireless cards which may be unsupported by Linux. What the ndiswrapper package does is to allow usage of the Windows driver for the card.
Below is a summary of my experience with the package. This is for Fedora 3, using DHCP. As they say, "Your mileage may vary."
I obtained the package from the ndiswrapperhome page.
I did the build, making sure the kernel source was present, as directed. (One does not build a new kernel, but one needs the kernel source.)
You can supposedly download the correct driver files from the ndiswrapper site. In my case, these were the files bcmwl5.sys and bcmwl5.inf. However, I later found that the first file, the driver, didn't seem to work. So, I got the Windows driver from my Windows partition, c:\WINDOWS\system32\bcmwl5.sys.
I put the two files in the directory /lib/windrivers, as requested. I then typed
ndiswrapper -i /lib/windrivers/bcmwl5.inf
This created the directory /etc/ndiswrapper/bcmwl5, with the two original files there, and others. I checked by typing
ndiswrapper -l
I did not modify my laptop's boot sequence to automate use of the package. So, each time upon bootup I type
modprobe ndiswrapper
This sets up my wireless device wlan0, and the pilot light for the wireless card comes on, showing that it senses a wireless access point. (Unless the access point uses encryption.) You can see the result by typing
iwconfig wlan0
If there are multiple access points nearby, the strongest one will be chosen. You can see what points are nearby by typing
iwlist wlan0 scanning
If you want to use a particular access point X, type
iwconfig wlan0 essid "X"
Note the quotation marks. Also, make sure to do this BEFORE running dhclient (see below).
Finally, you need to start DHCP, by typing
dhclient