Quest givers are in the additional room of the waking sand before you instance in to Minfillia's room. There are 4 of them each one leads to a zone you have been before but the hardest section of it... they all give a plethora of quests the lowest one is 10 the highest is 18. You should also be queing for dungeons at this point as your gear needs to start catching up for the endgame and the Tomes have started dropping in each dungeon.

They are out there you just need to find them.