Warning! This is a very old article, uploaded only for educational purposes.
This question has been answered many times at different sites and forums. Usually people answer in this way: 1-2 levels hunt bugs, 3-5 - spiders, 6-8 - wolves, 9-10 - scorpions, 11-12 - bears, 13-15 - skeletons, 16-21 - orcs, 21-24 - minotaurs, 24-30 - zombies, 30-36 - mummies, 36-42 - vampires and eyes, 42 and higher - dragons. In fact that doesn't answer where to hunt, but only determines certain levels' ability to kill certain monster. I have another opinion and I gonna place it here, separately for warriors and wizards.
Warriors don't have to care about mana, so the hunting place selection is easier for them. There are 4 kinds of monsters in tibia: monsters whom we attack with fire weapon, monsters who are better to be attacked with energy, also holy and ice monsters. On any levels both for warriors and wizards it's better to hunt ice monsters than holy, because ice weapon brings damage to enemy at each hit more than holy weapon. In the same way holy monsters are better than energy, and the energy monsters are better than fire. That is the first rule for hunting place selection. The second rule is an exclusion of any death risks while hunting. Don't hunt monsters which have a chance to kill you if you have a big lag, restart, have a call, 2 monsters attack, etc. There is no difference between hunting zombies or mummies because we use the same holy weapon for both. But mummies can kill even high levels, while zombies are mostly not harmful. So if you hunt monsters and afraid of lags that means that you will die sooner or later. Watch the example in bottom part of article. And the last, third rule - don't hunt certain monsters if your health point level goes up to a maximum while hunting even for a couple of seconds. So the monsters must be strong enough to bring some damage but which is not so serious for health. Those three rules are enough for warriors' effective hunting.
If your play wizard you must be patient, and never hunt monsters which warriors hunt at the same level. Wizards are weaker than warriors even at 3-4 levels and that difference in power just rises as the levels go up. The first rule of wizards' hunting place selection is the same as warriors'. the second rule is the same again - to exclude any death risks. The third rule is that the mana level must always be lower than health, so that you never stop hunting to recover your health level while you have enough mana to continue hunting. And the last, fourth rule - never hunt in the places where your mana level goes up to a maximum. So if your mana level is always lower than maximum it is ok and no matter how many monsters are in hunting place - 10 or 30. These four rules are enough for the nice wizard hunting. So the theory is over)
Let's have some numbers and compare zombie and dragon hunting. If I hunt zombies I do 4600 exp in an hour or 100 zombies an hour. Let someone of my level go to dragons and he will do 5100 exp in an hour or 50 dragons per hour. Each hour he will do 500 exp more than I make. Lets imagine that he managed to kill 14999 but be sure that 15000th dragon will kill him. In order to kill 15000 dragons he will spend 300 hours, make 1530000 exp and make 300 * 500 = 150000 exp more than I do, but when he dies he will lose more than 300000 exp. So you see that the main thing is non-risky hunting.
That's all I wanted to say about hunting. Of course it is too theoretical and sometimes players are forced to go to hunt in worse places because all good places are full of other players. And the last: don't hunt zombies at 1000 flowers island or I will hang you >:]
Edited by Tochki.su/TibiaME