wireless 802.11b fcc regs?

[Phillip H. Zakas]

does anyone know the fcc regs for broadcasting using 802.11a/b?  if you're
using the unlicensed spectrum (2.4 GHz) for xmit, do you need an fcc permit
to use the spectrum beyond a certain range?

I visited a company (www.luxul.net) and purchased a point to multipoint
antenna system capable of xmitting 512Kbps-11MBps up to 15 mile range (they
have an unusual 45 degree directional antenna system -- works great.)
anyway, thinking of launching a free encrypted wireless data service in
washington dc area, but unsure of fcc regs regarding the use of 2.4GHz
spectrum (don't expect free = super robust.)  also, am in need of two
antenna points...would appreciate suggestions other than the north clock
tower at georgetown univ.

phillip