There are more options to customise your Vampire Lord than perhaps any other Lord level character in the Warhammer Fantasy World (with the possible exception of a Dwarf Runelord that can spend up to 150pts on a very wide variety of runic item combinations).
The breadth of options is impressive and it's great fun designing Vampire characters. So much so that I have even taken to personalising my Vampires with names !
A Vampire Lord can cost anything from 205pts (for a basic lvl 2 wizard with no extras) to 730pts (which might be a lvl 4 wizard Vampire Lord astride
a rather fearsome Zombie Dragon !)
In brief here's a summary of your options:-
1) Upgrade your wizard lvl 2 vampire to lvl 3 (+50 pts, which does not come out of your Vampiric Powers or magic items points pool)
2) Mount your Vampire on a nightmare, hellsteed (a flying nightmare), abysall terror (a reasonbly hard flying vampiric monster, details to follow) or a Zombie Dragon (275pts worth of undead terror)
3) Give your Vampire up to 100pts of any combination of 18 Vampiric Powers (you could feasibly give a Vampire 5 powers)
4) Equip your Vampire with any one or more magic items from a choice of 29 Vampire items (including 8 magic items, 6 armour,5 enchanted, 4 talismans, 6 arcane items) plus the standard common items available to all armies.
That's what I call customisable !
The range of options available mean you can make turn your Vampire Lord into a maelstrom of close combat death and destruction or make him a true great amongst the spellcasters of the Warhammer world - enabling him to cast 8* invocation spells per turn, with a success on a roll of 3+** and the ability to raise units above their original strength ! ***
* if you include the Army's power dice.
** with the appropriate Vampire power (Lord of the Dead / Summon Ghouls / or Summon Creatures of the Night) or the Skull Staff arcane item.
*** if the enemy was unable to dispel then this could on average result in 19 new skeletons or ghouls per turn (approx. 24 if a Corpse Cart is close by). Or about 6 fell bat wounds, bat swarm wounds or direwolves.
The Vampire Lords are so customisable it's a bit difficult to advise on tactics because they can be adapted to any tactics you have planned for your army.
All I would say is that if you're expecting to face a High Elf, Lizardman or Dwarf army then it's best to invest very heavily in magic or not at all. A single good Vampire spellcaster can all too easily be negated by the above magically powerful Warhammer armies (magically resistant in the case of Dwarfs).
Errata: thanks again to blog reader AD2000 who pointed out something I had overlooked. This has now been corrected.