Available pets: dog, horse, raptor.
a) Dog - To get the dog you need 5 meat in your inventory. You can find the dog in Bareshade as a random event. (you'll have to do that event 5 times)
b) Horse - You need to build a stable, you can find the horse at River's bank while waiting. (The merchant and the guard will ask you to pick one out of three horse options)
c) Raptor - You need reptile's lure, can find them at Forgotten Temple. (easiest way to get reptile's lure is from the from the night witch after taking her ''tame the raptor'' quest.)