I need some advice on researching companies?

My boss has asked me to research the head of research, head of production and editor of some campanies to name a few they are:





alexander david


altium capital


banca IMI


bear stearns bnp paribas





So far all the ones I have looked on their website don't seem to have this information. Am I not looking hard enough or is there another way of obtaining this information, asssuming that if I call up the receptionist of the company they will not give me the information without a valid excuse.I need some advice on researching companies?
call the company! they'll tell you who the bosses are!