If your level isn't high enough to farm queen wiki wikis (I can't at level 73); another good farming spot is the Jaws of Judgement. Which, is right outside Rimedhal. From the dungeon entrance to the entrance for the second level. Every other mob has at least one wiki wiki and frequently you get three or four of them. If you use obliterate you can get 700+ jp per battle. The merciless souls mob also drops ghoulash, so you can farm indefinitely for free.

One area that's pretty decent if you're just starting out is the Sahagin beach just outside of the first town. Just gather some Fresh Fish from them then wait until night time to farm them for JP. Simply run from the west end of the beach to somewhere in the middle, taking on 2 Flans, 2 Sahas and another 2 Sahas. 2 more Flans spawn on the east end but is usually too much trouble to go all the way there unless the timing is off. Just spam attack commands. Guest char recommended if lower leveled

>>1 When you are strong enough, go to Savalon - underground resevoir- fight Mushussu (314 jp/ 530 jp with 1.7 jp up freelance skill) exit and entrance is very close as well.

The Leannan Sith method is so good. So much better than farming JP orbs from foraging or exploration.