CDC Health Information for International Travel 2008
Thanks to Resource Shelf, a great blog I've got feeding into my Google Reader, I learn about so many weird, wonderful things - this one's filed under part 2, as a useful source of information. The kind of thing that when you need it you really need it, and otherwise, you tend to forget it. The CDC Yellow Book for 2008 is an annually updated resource.
Things you'll find (picking almost at random, this resource is comprehensive:
Find health warnings by country, browse the table of contents, search for specific topics, check out the maps (what regions present the greatest risk of diarrhea? What vaccinations are required?) Find it here, bookmark it, use it when you need it - and bon voyage!