@Joker: Let me reread my books... hum seems you're correct.
However, again, increasing resolve and composure does increase your willpower score per page 95 of the core blue blook
"The only way to increase her willpower dots is by increasing her resolve and/or composure (see chapter 8 page 216 for more details)
It seems I was wrong about being able to just buy willpower. But again you can still raise your resolve or composure to get additional willpower dots because willpower is resolve+composure.