Petopia, useful guide on pets to tame: http://petopia.brashendeavors.net/
Lower level Hunters can save bag space by keeping one stack of higher-level food to feed their pets instead of carrying multiple stacks of lower-level food. Pets are not limited to the level requirements on food. Also, If your pet can eat bread, have a mage summon some for you.
Hunters can use mail aromor at level 40.
Hunters start being able to equip axes and bows or guns depending on race but can be taught to wield other weapons from in game NPC's called battle masters.
Always keep your pet on the highest level of happiness,noted by the green smily face next to it's hp/focus bars. This makes your pet inflict 125% of it's max attack.