Read a lot of the posts here and then some books. We picked up some good munis a few years ago and they're still paying an average of a bit over 5% tax free on our actual investment. We don't care if they go down in value because we plan on keeping them to maturity, for the cash stream. My thought, right or wrong, is that if we have a bunch of them maturing at different times, if interest rates go up, we can reinvest in higher return products as the current bonds come due. If we can control our personal rate of inflation by having no debt, that seems like a good plan to me.
Right now, we've got a bunch of money hopefull coming in from a real estate sale that we need to figure out what to do with--I wish I could get some solid tax free income on it at the 4 to 5% range, but don't expect to in the immediate future.