I recently began playing Skyrim (X360) and am a lvl 6 Nord. My question is, is should I go ahead and buy the DLC? Should I wait? Do I need to reach a certain point in the game before I buy the DLC?

Thanks!

If you think you'll like Skyrim, then sure why not. You can buy the DLC whenever but for some DLC (like Dragonborn) you must first reach a certain point in the main quest, which shouldn't take long. But the DLC can be difficult for low leveled players, so I suggest you play the actual game a bit more before trying out the DLC. There is tons to do in the vanilla game.