I just went through this search myself, now that the Microsoft Reader plug-in for Word no longer works (with the introduction of Word 2007).
In the end, I chose Mobipocket Reader, partly because it's an excellent e-book reader, and also because they provide a publisher-level e-book creator (as well as a simpler version). As a self-publishing author, and also as someone who just likes to take long texts along with him in a bookmark-able format, this was the perfect solution.
http://www.mobipocket.com/en/HomePag...sp?Language=EN