The RT61 chip set is found in a number of re-sold PCMCIA network cards, for example the Belkin G Plus MIMO card (v3 I think, other versions use other chipsets). Getting these cards to work under Linux has been a swine, NDISWrapper with the Belkin Windows drivers didn't result in any joy, the drivers shipped with Ubuntu didn't work and the downloads from Ralink weren't much better which is where most HowTo guides suggest you grab drivers form. Instead, at the bottom of the page is a link to the rt2x00 project
Starting with a fresh install of Ubuntu Feisty
You can configure the card with iwconfig, iwpriv or an application called RutilT. The documentation states that wpa_supplicant isn't supported which means that Wicd can't be used to easily configure yur network. RutilT seems to do an ok job as a replacement and is certainly more usable than the default gnome network manager package.
When it starts up, select your WiFi card (if necessary), let it scan and setup your profile much like the MS Windows Wireless manager.
Unfortunatly I still have issues with stability of Linux with the card inserted, I'm not sure if this is the laptop, the card or the drivers themselves. When the machine behaves, the above setup does work