Lightworks is now kurt of Beta and just published a 10-part series of tutorials.
Lightworks was, together with AVID, one of the founding fathers of more or the less affordable video editing. It's been available free of charge for a couple of years. Now, that it is out of Beta, it is available as a free "lite" version and a paid version for 60 bucks a year (50% discount for educational users).
Lightworks is given that cheap as the owner Editshare makes a whole mother load of money with their core business and selling a $7,000 Lightworks controller.