Level 49-60: Jr Yetis, or Grupins. Jr Yetis are for the lower levels(MapleStory gold) of this stage while Grupins are better for when you can two-hit KO them. They both give a lot of meso so profits are not a problem. Level 61-70: This period is often consider "Fizard Hell", as very few training places are offered. Grupins are the best exp you can get at this point. White Pangs are all right, but they have the most horrible maps to train on. Poison Wizards at this point should be leveling at the same place if they have Fire Arrow.
If not, they should either be training on Dark Stone Golems or Werewolves. Yetis and Pepe are pretty decent as well, but when they separate, they are a pain to kill, White pangs are a good option if you have posion and patience enought to train in Wolf Territory V. If you have Poison, you can also kill Death Teddies as you approach 3rd job. During the late 6xs, Fire users can go to Ghost Pirates or Death Teddies, though be warned: you will burn fast. The Three-Tailed Foxes are good exp in Maplestory, and provide excellent funding, dropping NPCable items that sell for a good price at NPCs drops often.
Since the launch of Boat Quay town, we the fizards have a new place to train on, the Ghost Boat V. There we can train with Selkie Jr, a virtually better version of the White Pangs, with low M.def, great Hp/exp ratio and great amounts of mesos. Level(MapleStory powerleveling) 70-80: You can train at Risell Squids if you have poison breathe maxed. If you max poison mist first, at level 75 you can go to Kentaurus' maps. It is suggested to train with the White Pangs/ Pepes/ Selkie Jr. Until you get a considerable level in Poison mist, or Explosion.