How difficult is it to keep a small herb garden?

I cook a lot and use a lot of fresh herbs, but they're so expensive! So I was thinking of growing a small herb garden of mint, thyme, Rosemary and maybe a few others... Problem is, every time I try to grow anything it dies. I have like, a black thumb or something! So, I was wondering what the difficulty level is for a small herb garden like this, if it would be better to grow indoors or out (I live in Bakersfield, Ca, so it's hot summers and very cold winters), and just any general tips someone more experienced than me :) thanks!