If your planing SP then:
1.Go for cons or frenzy, personal i found cons Barbs survive longer than frenzy and is more suited for untwinked chars.
2.Farm norm andy,norm Pindel(also good for xp), and at about 40-45 go for NM
3.After hitting act3 nm Mef your heart out
4.And finaly enjoy the game.
They are the two threads stuck at the top of the barbarian forum: "Barbarian Build Guides + Other useful Information; CHECK HERE BEFORE ASKING QUESTIONS" is the one you want. They are prefaced with the word "Sticky:" before the title.