First thing to do is just learn the software as best you can before spending your hard earned wonga on any commercial plug-ins.
One good site to go to for free plug-ins and news is
www.flay.com. I would visit this every so often just to keep up with developments.
A good site for lightwave tutorials would be:
http://members.shaw.ca/lightwavetutorials/Main_Menu.htm
You should be able to find some nice basic tutorials there that can introduce you to most aspects of Lightwave.