try kickass torrents or IsoHunt
Yes, Download steam, make an account, search L4D2 and download the demo from there.
l4d2 it has more zombies and its more funner.
yes
I have l4d, Not l4d2. But, there is no specific order. They're all different stories with the same people involved.
yes
you can't
!buy
yes
yes in verus
buy it
l4d
Novemeber 3rd