Here's a shout out to Austin Frakt and Aaron Carroll at The Incidental Economist for their blogging about health care.
In particular, Aaron Carroll's series on What Makes the US Health Care System so Expensive does a very good job of locating the sectors where the US health care system is more expensive than we would expect compared to other countries (it's less good at identifying why these sectors are expensive but we have to start somewhere.) The link is to the introduction to the series. Aaron's post on Red Herrings was especially good.
Austin has also put together a useful set of powerpoint slides on the US Health Care Crisis. He invites you to steal these for your classes or talks or just to read.