4) There is a really quick and easy way to get a unique artifact, Azura's Star, which is arguably the most powerful item in the game which will let you ignore the whole Soul gem system. Basically, it is a re-usable Soul Gem that can hold either a Grand or Black soul in it (you need to choose when you get the item, and the choice is permanent). Since Black souls are all over the place, you should choose this option. To get it, simply talk to a bartender until you get a rumour about the Shrine of Azura. Go there, talk to the chick, she sends you to talk to the elf in Winterhold, go to the dungeon he tells you about, get the Star and then return to the elf. He does some magic, you defeat the boss and you will have the best item in the game. Your enchants will now be extremely powerful.