"Is it worth spending my money on the books and DVDs of celebrity artists the likes of Bob Ross, Bill Alexander, Frank Clarke, or Darrell Crow produce on their painting techniques? Or it is simply trick painting?" -- Siobhan
Any of these guys' techniques are one way to start painting. But they generally approach painting focused on one technique (or trick), so at some stage to develop your own style and expand your repertoire you need to expand your approach beyond what you've learned from them.
I wouldn't call it trick painting, it's more a question of if a technique works for you, then why not use it? I've had great fun on workshops trying out new approaches; some worked for me and I incorporated them into my painting, others were a disaster.
I remember one where you took any three colors, in three tones (light, medium, and dark), and painted in the initial shapes. Then repeated the process with another three colors, gradually putting in more and more detail. Although I had no problem with the concept, my painting just got worse and worse. The poor tutor got quite desperate and on the last day sighed wearily, "This isn't working for you, is it?" I just laughed and agreed, saying he really shouldn't worry as I'd had fun anyway.

