You start with boots of speed +3 pots or Elixier of Brilliance +6 pots (take a sololane, it wont be funny to be on a duo lane as vlad)!

the most important item you need is Hextech Revolver
(dont rush Will of the Ancients exept you are in base and you cant get another item as well)
after this one you´ll get Spirit Visage and cdr Boots

next one is Rylais Scepter or Zhonyas, most time i prefer Rylais cause of the slow on Q

but Zhonyas is exremely strong too,you can go in with ult use pool and use zhonyas after
(i think this is the strongest item for teamfights)

the next step is to become more tanky for teamfights you dont wanna drop instantly after using pool right?

i love to play with Force of Nature but if you like to do more dmg and take another aura for your team go for Abyssal Scepter

the last item you buy is Rabadons Deathcap sell Spirit Visage and go for it!