At $8000 per, http://interorbital.com/TubeSat_1.htm
is probably about as cheap as it gets.
edit: Do note, these things are pretty limited (you know, as far as personal satellites go...) and likely not at all suited for the purposes proposed by the guys in the OP. But for anyone wondering "what's that cost, my own satellite?": there's your answer.
edited 6th Jan '12 9:44:17 PM by GreatLich