Good luck on finding the heartbeats, girls!! Remember, eat something about twenty minutes before... and also, sometimes you'll be in the right location and you won't hear it, you'll need to just rotate and shift the direction of the wand. Also, most people I have spoken to have heard it a little bit to the right of the middle of the stomachs. That's where I have heard it as well.
On another subject, have any of you been drinking soda or diet soda? I am NOT a soda drinker, but my office fridge is stocked with them and I am dying for a Fresca (caffeine-free, but has aspartame). It's not good for you, that's for sure. But I'm wondering, is 30-something grams of sugar better than a little aspartame?