I know a lot of people will probably already know this, but the mine located right before Riverwood, Embershard Mine, is an extremely easy mine to explore with only a few Bandits. There are many valuable early items (magical ones!@!@!) and lots of useful smithing items as well! It takes very little time and there is almost no risk. If you need quick gold in this game for spells or whatever you please, give this a shot. Just a tip, and sorry if you already knew this, just trying to help