If you are looking for small species they do have some dwarf tarantulas. One that actually is only 1"-2" as an adult is the Cyriocosmus elegans-Trinidad Dwarf, another good choice is the Paraphysa scrofa-Chilean Copper that is about 3"-4" and is pretty docile or the Paraphysa parvula - Chilean Gold Burst. Then you have the Euathlus sp. "Flame" that also is small. Not to be confused with the Grammostola rosea - Red rosehair.
These that I have suggested usually won't bite but if it has a mouth anything can bite. If you get bitten it is not that bad, about as bad a bee sting. The injection site would hurt because the skin was punctured. No they do not take the venom out of the tarantula. This is how they catch their food.
These that I have listed do kick urticating hair, but not all species of tarantula have these hairs. Arboreal species like Avicularias actually shoot their "poop" at you and run away. Old world species do not kick urticating hair, but they will bite more readily and their venom is much more potent then the new world species that I have listed.
I hope that this helps you in your quest for a tarantula.