If you want to anti-sorc, cold resist won't do you much due to their Cold Mastery.
Of course, you'd need at least positive resists...then you can use some absorb gear such as Raven Frost ring.

*cough* If you just want to build a barb for high resist, and not taking him to dueling or anything...use natural resist.
Lv 20 gives about ~67% all resist.
UM your Shield/Armor/Helm for extra resist.

Tell me what the barb is for...PvM, PvP, or...Gallery