They are both trained by your hunter trainer. You may have missed them. Steady shot is under Marksmanship and I'm pretty sure that Kill Command is under BeastMastery
Steady shot (Level 62) is a 1.5 second cast shot that doesn't reset your shot timer (so if you have a 2.9 speed bow, you could fit a steady shot in between your normal shots). It essentially doubles your DPS, because you can get two shots in the same time it used to take 1. It's also really popular because it doesn't take a lot of mana.
Here's a full article on it. Kill Command (Level 67) is a skill that affects your pet. When you make a critical hit, it lights up the button, you hit it and your pet will get in an additional (and strong) attack on top of its normal attacks.
And some more info on it here.