Which Broadcom Card?
You can use
1. bcm43xx.ko for old ones and b43.ko for new. These are kernel modules, and are sometimes blacklisted. You need a kernel 2.6.27 or later for these. if it's on usb, you also need ssb.ko
2. Broadcom's proprietary driver. ymmv. A Bitch to install
3. ndiswrapper and some windows driver.
http://www.linuxwireless.org