there are a bunch of jewish guide books available . i read around three of them, and by the time i took the jewish tour i already knew 75% of what he told us. (it was useful though to have him point out things i wouldnt have realized.) that was the jewish ghetto tour. with regards to the coloseum/forum tours, i booked a regular cheap non jewish tour and told the guide at the beginning that i was jewish and would appreciate any sort of jewish perspective to which he replied that he would be talking about that anyways. (arch of titus, coloseum etc.) and lastly ive heard from friends that the jewish vatican tours were a complete waste of time/money, that it was basically a regular vatican tour plus they took you to a place where there are jewish artifacts, which i did on my own. (it was a little difficult to find but if youre interested, pm me)