Of all the years I’ve been doing networking, I never setup a wireless printer until today (12/18/2010). I own a HP C4580 which has wireless capabilities. The help instructions were no where to be found (the book you get) so I tried to figure out via the web. My “search foo” was off. After an hour, here is my instructions. Hint, Hint HP.
1) Connect wireless laptop to the HPSETUP
2) Wait about 2 minutes and get a 169.x.x.x address
3) Print network configuration on the printer (make sure the wireless option is on)
4) Browse to what is printed on the config
5) Setup the printer (advanced tab) with the SSID (same as your local SSID router), type in WPA key.
6) The laptop you are using will automatically reconnect to your wireless router, mine did at least.
Took literally 2 minutes to hookup 2 other machines in my house to the printer.