Get hold of Martin Evening's book on Lightroom 4. Highly recommended and it will remain useful for some time.
I don't like video tutorials because I never seem to work at the same pace as the presentation and I don't like pausing and replaying bits. A book I can use at my own pace and when I'm away from the computer.
Victoria Brampton has a Q & A how to book but my copy has yet to arrive. It is said to be pretty good too and the style is quite different from Martin's book, so they ought to complement each other.
I like Victoria Brampton's Q&A pdf book. Very easy to search for topics. Just type in what you want to find out in the search box and you will get what you are looking for. Simple and easy.