802.11a, b, and g have the same effective range (~30m indoors). a is slower for transferring data (6-7mbps, I think?), but it has twice the frequency, which means half the wavelength so it seems to me that it would punch through walls easier. Also, because 802.11a isn't in the ~2.4ghz range, it doesn't have as many conflicts with other radio-based equipment (like cordless phones).
In government, we were seriously considering 802.11a for mass deployment, because:
- The range is the same
- Many cards don't support it, which gives security by obscurity
- Most other people don't use it, so less interference
- Less tools use it, so again less interference
I can't suggest specific cards, though.
In one laptop, I use my Intel Centrino, which works beautifully under Linux, supports 802.11b and g.
In my other laptop, I use a Microsoft MN-520 PCMCIA card, which also works beautifully under Linux. Only supports 802.11b, iirc, but it was cheap ($10, used).
I have also used both cards under FreeBSD with little problem.
