I always have trouble taking pictures of people. I hate it. I feel awkward, I always wonder, am I stealing a piece of their soul? (Not really. I'm pretty sure people keep their soul regardless of photography.)
Even when I have express permission (which I recommend getting) I still often can't quite bring myself to take a picture. A good example of this was when Evan and I were in Myanmar, and being herded around like sheep, as tourists often are in Southeast Asia. We were taking a day boat trip on Inle Lake, and one of our 'stops' was to see a few ladies from the Long Neck tribe. Basically, the entire purpose of the stop was to take pictures of these women. And they invited me to.
But I couldn't do it. It still felt rude to me. As though by taking a picture of them I was saying, "Gosh, you look sooooo weird. I have got to show the folks at home a picture of this."
So, sorry, I don't have a picture of them to show you. But honestly, that's okay with me. Google Long Neck Tribe, and you'll see a ton of pictures very like the one I might have taken. It wasn't going to be Art.
Recently, however, I discovered a new solution to my shyness: shoot from the hip. People get self-conscious when you bring the viewfinder to your eye. What was a natural smile or pose turns a bit awkward.
So, instead, hold your SLR like a point and shoot. Or even lower. If you have Live View, this is a great time to use it. What I do is turn Live View on until I see a framing I like, then I turn it off but keep the camera in the same place, then use the shutter button to autofocus and take the shot. And if my subject's not looking at the camera, or can't hear the shutter, they don't even know I took a picture!
I used this technique recently to take the shots of the students in the classroom. And I ended up with a lot of interestingly composed frames that I might not have had otherwise.
It's not a perfect technique. And I usually have to take a few shots to find a keeper. But it's better than nothing, which is what I've often ended up with before. Try it! Let me know if you do, I'd love to hear how it works for you.