I love playing barb and I love playing hardcore!
I got to inferno with the first barb i made and i've been trying different builds since nightmare and i think i just got a really good build and i can solo act 1 and do itens/elite/boss runs with no difficulty.
The first thing you have to think when you get to Inferno with a barb is this: you will be constantly taking lots of damage from melee atackers so you need a high defense, high resists and high life steal. If you have a awsome one hand wep with life on hit (300+), all armor pieces with lots of all resists (40+) and a good block % shield (25%+) you are good to go, BUT if you are like me, still trying to farm good itens, the build in the link below might be really good for you:http://eu.battle.net/d3/en/calculator/barbarian#WVXTkP!deb!ccabcZ
Let me explain the skill in this build and the itens im using.
I use a one hand wep with 1.34 atck speed and doing 680 dps, got a shield that has 19% block and 790 armor, all my armor got at least 20 resist all (except rings and amulet that doesnt have all resists). Its not the best equip but its not the crapiest itens for HC. I didnt pay more that 1kk in any item yet in AH.
I do 10k dps, got 52k life, got 65% dmg reduction and 59% (at least) in resist all after the Warcry buff (with Impunity rune).
Frenzy (Maniac) - you can use Maniac for more dgm (i get to 12k with it) or you can go with Sidearm rune if you want more AOE, but for AOE i got Earthquake if things get difficult and also Revenge. Frenzy gets more atck speed that is great for life steal and life on hit (a must for HC inferno!)
Revenge (Provocation) - as this build you won't need that much fury, you can go for the Provocation rune instead of the Vengance is Mine. the 30% activation it's a must when you get surrounded and it will be your main healing skill (5% life total per hit it awsome!), just remeber to use it when you need it, do not use all the time when it activates, try to hit at least 2 creatures.
Leap (Iron impact) - only for running and fleeing situations! the armor bonus it's a must when running and low life situations, your dmg reduct goes from 66% to 84% (i think), just be aware with jailers, but for that situations we have Wrath of the Berserker.
Earthquake (The Mountain's Call) - this is a great elite killer when combined with Super Sayian mode (Wrath of Berserker) and when your Frenzy stack is max (5 stack), your dps gets to 35k and your dmg with Earthquake goes nuts. even with the life steal debuff from inferno, it's almost impossible for you to die while the skill is on and hitting the elites (and also with the Bloodthirst passive). use Earthquake always when you find an elite group and always remeber to use Super Sayian mode. you can use Earthquake also in difficult normal monsters situations, like those annoying Wretched Mothers in some dungeons.
Warcry (Impunity) - once you get to 50k+ life, you won't need the extra 10% life buff from Invigorate, you just need to stack resists and impunity is the rune to go in Inferno. just remeber not to stack that much life (70+ is too much) and than you lack dmg and you can't kill anything...
Wrath of the Berserker (Insanity) - i guess every barb in inferno uses this skill, it's your elite/boss killer... you get mov/crit/atck speed/dodge and 100% dmg with Insanity, that does a sweet combo with Earthshake. remeber after you kill an elite group to wait for your cooldowns to finish before going after another group, just walk around map opening some chests, repairing itens and chilling in town.
Superstition - a must for those arcane enchanted and all non-physical dmg. every barb must use this one as it gives a buff to your resists against those kind of dmg.
Nerves of steel - much better than Though as Nail as it gives you more armor and your build is not going for thorns dmg to mobs. more armor = more dmg reduct so... go for it!
Bloodthirst - well, this one you will use untill you have amazing life on hit equips (600+) that you can get from weps, rings and amulets. this passives workes great with your Wrath+Fenzy+Earthquake combo for elites when your Revenge doesn't activate. this passive you can latter change for almost anyone of your preference... if you want to go for more dmg and fast mob killing, go for Weapons Master or even Berserker Rage (this build doesn't spend that much Fury and you will be at max fury almost all the time)... if you want more survivability, go for Relentless (if you constantly get in low life situations) or Though as Nail for even more armor... or if you don't like to wait that much before going to the next elite group, just go for Boon of Bul-Kathos for lower cooldowns.
Hope this can help all barbs out there that are getting to Inferno right now and are still afraid of running it.
Please comment if you find a better build or even better items combinations.