Once your Barbarian reaches around level 75 (perhaps with a help of a leveling build), you will be in a prime position to pick and work toward your endgame Build. Keep in mind that your Build will not only define your skills going forward, but also your optimal weapons and armor.
Below you can find some of the best Barbarian builds for Diablo 2.
Whirlwind Barbarian
The most commonly-used Barbarian build, this build relies on the Whirlwind skill to deal damage and stay mobile, as well as skills like Leap Attack for increased mobility, and various shouts or masteries to boost effectiveness.
War Cry/Singing Barbarian
A Barbarian build that lets you have all the melee-oriented combat prowess of the Barbarian, while also making you a hybrid caster. Thanks to powerful stunning Warcries like… well, War Cry, and self-buffing ones like Battle Orders, a Singing Barbarian is a surprisingly tanky, powerful build.
Berserk Barbarian
What is a Barbarian for except for hitting stuff. Really hard. And that is what a Berserk Barbarian focuses on: the rage damage created by combining weapon masteries like Mace Mastery with the damage boosting Berserk skill (together with some Warcries). As long as you have the gear to make it work, this is the build for classic warriors.
Resources and Links
Icy Veins
Barbarian Class and Build Guides
Fextralife Wiki
Barbarian Builds
RankedBoost
Barbarian Builds Ranked
Wowhead
Barbarian Builds and Gear