Until I wire my house for Cat6 I'm stuck with using wireless to connect my PC upstairs to our router downstairs.
I've just got the Virgin Media 50Mbit service (which actually does pretty close to what it says on the tin) and they gave me a free DLink DIR-615 wireless N (300MBit) router and a Netgear WN111v2 wireless N USB adapter.
The USB wireless N worked fine under Windows XP using the Netgear driver CD but I mostly use Ubuntu for coding and found that this did not work out of the box so here is how to configure Ubuntu 9.10 (Karmic Koala) to get online.
dmesg identifies the USB nic as an Atheros AR9170 and luckily Ubuntu 9.10 and higher have the driver for this included.
The programs you will need are (you *are* using WPA2 encryption right?):
ifconfig, iwconfig, wpa_supplicant, wpa_passphrase
First you need to generate a hashed copy of your pre-shared key (PSK)
wpa_passphrase MY_SSID MY_KEY
This generates part of your wpa config file
psk=hash of my key
Next, you need to create a wpa_supplicant config file /etc/wpa_supplicant.conf that includes the part you just generated
psk=hash of my key
now issue the following commands (better still, put them in a script)
sudo ifconfig wlan0 up
sudo iwconfig wlan0 essid MY_SSID
sudo iwconfig wlan0 mode managed
sudo wpa_supplicant -Dwext -iwlan0 -c/etc/wpa_supplicant.conf -dddt
This will start up wpa_supplicant in non-daemon mode (running in the foreground) so start up another terminal and run
sudo dhclient
This should get you an IP address from the router and you should now be in business!