Brawnwrong: Baby steps! Start with crowds, distant, and/or unaware people, where your subjects won't feel singled out, giving you less need to "man up" as you put it. Each time you take a shot, it becomes easier, and soon you'll be sticking your camera up strangers' noses like a pro.
I did a lot of street photography in October. Random scenes from daily life in Trondheim, Norway, using a D40 with a 35mm prime: