If you're local and have trees that need work, I highly recommend Arthur Ratliff Tree & Stump Removal. I called them on Monday afternoon about a half-rotten tree that was not only right next to the house; it was actually in the middle of our deck! He came out that night to see it, came back the next morning to see it again and make an estimate, and he and his crew were back the next morning to take it out, along with a branch that was rubbing on the roof and an old dead tree that had just fallen. They were fast, clean and efficient, and it cost less than I was expecting. Don't get me wrong, this isn't a budget outfit, but they're reasonably priced considering the quality of their work, which was important, given the location of this tree. But I very much think it was worth it.
BTW, I heard about them through this article in our local paper, which is proof if proof were needed that PR is more effective than advertising. And Christie and I have both recommended them to friends with tree problems, so word of mouth is obviously a big part of how they do well. Which is why I'm passing this on.