What the heck does sell to witch doctors. I have no clue what their main attribute is.
There are basically two witch doctor schools once you hit inferno:
The 1st is centered around poison darts, attack speed/crit chance/crit damage, and run speed. Kite everything, shooting for max DPS, max IAS/Crit, and max run speed. They want Int, attack speed/crit chance, crit damage. Variants swap out darts for spiders.
The 2nd is centered around Acid Cloud or Rain of toads and is a tanky build. They want Int, Vit, Resist All, %life, HP Regen, and Armor. Int itself isn't a big priority although I listed it first. These guys are about surviving as long as it takes to whittle the target down so DPS isn't that important. I'm playing this build right now and I can even stand there and tank the enraged DoT if I have to.
Both schools benefit from mana regen on Helms and Ceremonial Daggers, the first school will also want it on offhand Mojo. Both benefit from Life on Hit on anything. Both benefit from Crit chance/crit damage.
Most other witch doctor builds in Inferno are just variations on these two themes.
The top dollar items should be ceremonial knives with max damage, max mana regen, good life on hit, and a socket. A close runner-up would be a helm with max mana regen, high int, high crit chance, high magic find AND a socket.
Oh, one last thing. A Tank Doctor will pay good money for a low block chance shield that a barbarian would ignore. The TD needs the armor a lot more than the barbarian does, so they make good stat sticks. Armor + vit + resist all + %life/HP regen/etc. even with low block is still a really good offhand for a tank doctor. Playing this build getting 850 resist all is trivial, getting 8500 armor to match it feels nigh impossible.