I use this build. Can farm Act 1 Cath T4 easily using cheap gears. Can also do Mira run in T5.
http://us.battle.net/d3/en/calculator/barb...YhVj!YacZcb

Weapon - Skorn (I bought for 7m, 1.3kdps, OS, 190%CD, 300+str)
Belt - Mighty Belt with LS if your skorn does not have LS (Also cheap <5m)
Pants - The leg pants that gives +25% dmg while moving
Chest - Get decent rare/leg with 3 slots - gem diamond (OP now)
Others - Get leg/rares that increase lightning dmg or WW dmg