3 monitors crossfire

Currently running 2 monitors off my 6570 ( one hdmi, one vga) which is crossfired (dual graphics) with my A8 APU. I have a third monitor that I would like to connect.

First, do I have to get another Graphics card to do this?

Second, If i get another 6570 will I be able to crossfire just the two 6570s and have one monitor connect to one and two to the other or will crossfire be disabled?

I am not trying to use eyefinity. I just want to have an extended desktop like i am currently using with my 2 monitors but with 3. I have one monitor which i use for gaming and would like to have the other two for web/email etc...