Where to go to get door properly aligned...
I don't think that was the constructive answer the OP was hoping for........Rude72, please excuse him.
So, as you stated you a newbie and believe me even an experienced person may have a difficult time with the tedious task of adjusting doors and gaps. Make sure the hinges and pins are good and if it's close, get a friend to assist you. There is equipment to help hold doors too, but you could also use a floor jack with a few blocks of wood on the bottom of the door (not the lip). Take your time, you will get frustrated. Walk away and give it a shot with a clear mind. The adjustments should be pretty straight forward once you see the hinges and how they work. Again, use patience and don't go slamming the door shut until you get it right. If the doors sags, seek out the friendly member here who offers a rebuild service (sorry, his username escapes me). I have used him for hinge rebuild.
If all else fails, a bodyman should be able to help.