I use a Belkin BLuetooth PCMCIA adapter card. It's an older generation one and causes me some problems. Surprisingly, too, because Belkin is usually a provider of top notch stuff. But the driver installation is tedious (takes a LONG time, as much as 15 minutes as it scans each COM port and installs a separate driver for each), rife with install errors (you have topress ignore about 20 times, so you have to SIT through the fifteen minutes) and the final programs it installs are intrusive.
It doesn't even work that well at connecting to other BT devices. But it works with my printer, so I still use it on occasion.
I made the mistake of buying a Motorola phone that was supposed to have BT, but Verizon crippled most of the BT protocols and you can't swap data from the phone to the PC, so I really am not getting anything out of Bluetooth in the real world.
Bluetooth is a dying standard, partly (I think) due to poor integration with hardware, limited distance and a complicated user experience. I'm not sure I would invest in much of Bluetooth any more, because I would bet it's not around in a few years.