Does anybody know of any good tutorials online for mending clothes unobtrusively?

I'm not a complete nitwit with a needle and thread, but I haven't had much serious instruction. I can do things like replace buttons, hem, patch, and sew ribbons onto pointe shoes just fine. (And sometimes the stitches are actually even!) I've done some basic alterations just fine. But when it comes to mending my favorite pieces of clothing when they get torn, I haven't yet learned how to do it so it's not that visible.