[RPG] How is the Ogre’s greatclub damage constructed in Pathfinder

The bonus is applied to every damage roll the Warlord's allies do.

In order to comprehend what a damage roll really is, read Rules Comendium, page 222. To short it up, any expression of dice (or [W]) that you can find in a power, feat, monster stat block, etc. The following are examples of damage rolls.

• 2d8 + Wisdom modifier damage
• 1[W] + Strength modifier damage
• 3d10+4 fire damage

Damage roll modifiers can be applied to such expressions. If a power, class feature or else allows you to perform multiple attacks (like the Ranger's Twin Strike at-will attack power) or multiple damage rolls, the bonus damage is applied to all relevant expressions involved.

However, any expression referred as extra damage is itself another modifier to a damage instance. See Rules Compendium, page 223.

Extra Damage Many powers and other effect grant the ability to deal extra damage. Extra damage is always in addition to other damage and is of the same type or types as that damage, unless otherwise noted. Because of this rule, an effect that deals non damage cannot deal extra damage. However, a power doesn't necessarily have to hit a target to deal extra damage - it needs only to deal damage to the target.

Under this category fall many Strikers' features, such as (but not limited to)...

• The Rogue Sneak Attack,
• The Ranger Hunter's Quarry, and
• The Warlock Warlock's Curse.

Hunter's Quarry may be used once per turn; let's suppose the Ranger uses Twin Strike, hits both times, applies Hunter's Quarry (1d6) to the first attack, and benefits from his ally's Warlord's Strike for another +4 bonus damage.
1^st hit: he deals basic weapon damage [W] (damage roll) +4 (bonus damage) +1d6 (extra damage).
2^nd hit: he deals basic weapon damage [W] (damage roll) +4 (bonus damage).

Note that the extra damage from Hunter's Quarry is not modified by the Warlord's bonus: it is a modifier itself. For many aspects, you can consider it a still-to-be-rolled static damage bonus.

He just uses the +2 for the short sword melee attack. That site has already calculated the attack bonus. As you calculated, the goblin is getting is +1 from BAB, +0 from STR, and +1 from size, for a total attack bonus of +2.

For comparison, note that he has a +4 with his shortbow: +1 from BAB, +2 from DEX, and +1 from size. (You use dexterity rather than strength for ranged attacks.)

slang definitions: BAB = base attack bonus, STR = strength, DEX = dexterity