Man, this is really starting to bug me
I opened up my 5670 and found that I have a WL-352BW, which I can't find listed anywhere. The closest thing I get is a WL-352 that is 802.11g, but mine is b. Well, I took another number off the card, 'BCM 94301' and then took a look at my drivers. Well, Broadcom made my drivers, and I was able to find a wireless card that looked exactly like mine called the BCM94301 made by Broadcom! The only thing is, Broadcom doesn't give any drivers. My suggestion, take another look at your card and post all the information you can. I'll try scouring the internet to help, since I have plenty of spare time over the next few days. If you can find the manufacturer, try contacting them.
I contacted Sager for information about where they get drivers and why they don't update them on their website. My belief is that they probably use a variety of cards so they send out the drivers on individual floppies. Once again, the best bet is to figure out who made your card. Maybe we can catalogue different suppliers here to save some others the trouble.