Well there is Miletich Fighting Systems, thats produced single handedly the most UFC Champions in History I believe. There is The Hughes Intensive Training Squad, thats going to be a big camp of the future. There is Jeremy Horns Elite in Utah, havent heard much from them, but still. Matt Hume Pankration in Washington State is quite large, Brazillian Top Team, and its Sister American Top Team are two of the most well known, nationally and internationally. There is of course Gracie Barra here, there, and everywhere.
Chute Boxe is supposed to be another large camp, yes i've heard of Greg Jacksons camp aswell, but thats riddled with scandal at present American Kickboxing Academy...likewise not in the UFCs good books at present, There is Team Quest, Xtreme Couture, both doing well....in England we have Wolfslair, that has international fighters with it
I wouldnt rank BJ Penn so highly because I dont think the camp is good, its only him, likewise with Urijah Faber, these are one off people who are more of a name then their camps