Hadn't seen the topic as I'm not a wave rider (too old and too scared

)
Nouméa (capital city) has a nice wave spot that only operates at high tide, called Magenta, located next to domestic airport which is good as the kite surfers aren't allowed there.
For big wave riding you have to team up with the locals as it all happens on the reef (we have a reef barrier that goes all around our lagoon)
You either need a boat or take a drive to the ouano surf camp (1.00h drive) and take off from there to the reef just in front, some massive glossy waves.(the one al mc leod posted)
Season wise you're best off from october to may, tradewinds and warm water.
Just check out this guy's website for awesome pics :
patricemorin.com/spip.php?article1240