I get emails from around the world from people in panic-mode over Lightroom-related issues. Some of these can be easily cured, but sadly, some are fatal. I do consulting in-person and over the web and phone/Skype, so you can always contact me to help you work through your issues (sorry, yes, that was a blatant plug), but I thought I would recommend some preventative medicine first. It is a chance for me to pull together some older posts that you might not otherwise come across.
Once you understand how Lightroom works you may think some of these are silly, but they are real misconceptions, and many real tears have been shed. It is understandable, given that Lightroom works differently from other photo programs people have used.