there is one barb that fits ubers quite nicely and thats a frenzier. WW is useless for it cos of no ctc and the other ias is too slow. ash has done quite a nice guide for a frenzier on these forums. the ias works well for triggering life tap and ive found him so much more fun to use than my smiter. i cant remember whether Ash updated the guide to include uber killing, so heres my 2 cents....
Arreats or Guillumes face (for CB-use this instead of arreats if u dont use goblin toe))
Fortitude (the enhanced damage is useful whereas its not with a smiter)
eBotD Ba-ias is invaluable there and its such a cool weapon
eDeath (many will argue about this choice, and i will say they are probably right in saying beast instead-i just hate having to go to town to repair the beast half way through OR ive heard that last wish is nice for uber killing although never tried myself)
DRACULS GRASP-vital for lifetap triggering
gores/goblin toe-goblin toe have more CB by 10% but not much else
belt is up to you-i use perf string of ears.
you shouldnt have to replace arreats with guillumes for extra CB since there is 50% on death (40 on beast) and 25% on goblin toe (15 gores) which is plenty for ubers, but i included it as an option just in case you strongly disagree with my weapon choices
Skills and stats in ashs frenzy guide are still relevant so just refer to him on that point.