Almost no passives show up in the char screen until your "+AllSkills" level changes (i.e. Skill shrine, BattleCommand, items, join a game, etc). Sorry for that inconvenience, it usually only affects new characters since their level changes several times a game. I'd recommend picking up a 2-handed weapon (they all spawn with +1AllSkills) and keeping it on switch, so when you place a skill point you can just weapon switch to and from that weapon and move on. For a Barb, BattleCommand is available at level 6, and is a good solution.
Ranged Mastery benefit bows, crossbows, and throwing weapons (during melee and thrown).
If you check the WhiteWeapons webpage, you'll notice that just about every weapon has an automod related to a hidden oSkill. That oSkill determines which mastery it benefits from.
The WeaponMasteries in v1.7 apply their +%ARating and %CriticalStrike regardless of which weapon you're attacking with, but only weapons of the appropriate type spawn with the appropriate Mastery oSkill. For example, you can have Lvl20 OneHandedMastery, but only 1-Handed weapons have the hidden oSkill that gives your character +%ARating and Crit for the points you placed in OneHandedMastery. If you had Lvl20 TwoHanded and OneHanded Mastery, then all of your attacks would gain the +%ARating and Crit from both skills regardless of which weapon is currently attacking, but only if you were able to hold a TwoHanded weapon at the same time as a OneHanded weapon. The swords that have +Paladin and +Druid skills count as OneHanded swords (as shown in the WhiteWeapons webpage).
Possible known exploits (they're not game-breaking exploits, since you'd have to spend a lot of skill points for the extra offensiveness, leaving you pretty fragile, but I suppose 1-point investments could be worthwhile):
- Equip a OneHanded weapon with a ThrownWeapon (Axe is the way to go here since their average damage is highest), you'd possess the oSkills for OneHanded and Ranged Mastery, so could gain benefits for both weapons from both skills.
- Find an AkaraRing with +PoleArm (aka OneHanded), Throwing (TwoHanded), or Spear (Ranged) Mastery. Those three Barb skills were the ones overwritten to provide the PassiveState that actually gives your Barb the stats from his weapon masteries, but they still show up with their old names since I never actually renamed them (didn't think anyone would see). That ring would allow the stats of an extra WeaponMastery (probably 20%Crit, 50%ARating end-game).